Compare Prince Hal to Hotspur in Henry IV, Part 1.

I would add that perception is a huge theme in this play, and must be taken into account when comparing these two characters. We see how the king perceives Hotspur (as noble and valiant and worthy to be a prince) and his own son Hal (as dissolute and uncaring). At the same time, the audience is given a peek at Hal's intent from the beginning, when Hal soliloquizes that he has an unannounced plan to throw off the inappropriate behaviors and appearances when the time is right: 

Yet herein will I imitate the sun,
Who doth permit the base contagious clouds
To smother up his beauty from the world,
That, when he please again to be himself,
Being wanted, he may be more wonder'd at,
By breaking through the foul and ugly mists
Of vapours that did seem to strangle him. (I.2)

At the same time, Hotspur is a valiant, honorable man--with a nasty temper and sometimes, the cunning and tact of a three-year-old. He has focused all his energies on being a great warrior but he throws temper tantrums. He also sees no more than appearance in his enemy, Prince Hal, causing him to grossly underestimate the heir apparent on the battlefield, costing him his life. Hal may compliment Hotspur, as symatsuoka says, but that bespeaks his own graciousness and nobility more than Hotspur's worthiness of his praise.

Compare Prince Hal to Hotspur in Henry IV, Part 1.

Hal, who is otherwise known as Prince Henry of Wales and the future King of England, is very different from his counterpart, Hotspur. Hal enjoys a good time, and expends his energies plotting pranks with an unsavory element at the pubs. Although he is being groomed to one day be King, Hal avoids his responsibilities in the royal court. He is a work in progress, and the reasons behind his outlandish behavior are much debated by critics.

Hotspur, whose real name is Henry Percy, on the other hand, is an inarguably honorable character who stands in stark contrast to the more lackadaisical Hal. The son of the Earl of Northumberland, Hotspur is valiant in battle and actively seeks recognition for his military prowess. He is charismatic, brave, and loyal, exhibiting a sense of purpose and seriousness that Hal appears to be sorely lacking.

It is a tribute to Hal's perceptiveness that he recognizes the strength of character possessed by his rival. He says of Hotspur,

"I do not think a braver gentleman,

More active-violent or more valiant-young,

More daring or more bold, is now alive

To grace this latter age with noble deeds" (V.i.89-93).

Hal also astutely recognizes Hotspur's tragic flaw - although Hotspur is complex and unfailingly noble, he, unlike Hal, does not have the ability to live in the real world of his times, a world which Hal describes as "the vilest earth" (V.iv.91).

What characteristics make Hotspur a better leader than Hal in Henry IV, Part I?

Hotspur—or, Henry Percy, to give him his real name—is the son and heir of the Earl of Northumberland. Around the same age as Prince Hal, he also has a kingly bearing about him, as one would expect from a scion of one of England's greatest noble houses. Whether that would necessarily make him a better ruler than Hal is a matter for debate. Certainly, Harry Hotspur possesses a number of qualities that would make for an excellent king. He is incredibly brave in battle, is charismatic, and has a forceful personality that easily binds others to his iron will.

Yet at the same time, Hotspur has many flaws. For one thing, his physical courage easily spills over into outright recklessness. He is rather impetuous, his fevered mind going in several different directions at once, making it almost impossible for him to stay focused on anything for very long. A lack of maturity and sound judgement is also a problem. There can be no doubt that, on the battlefield, Hotspur is second to none when it comes to sheer courage. After all, that's how he earned his nickname. But because of the serious character flaws we've just been considering, he is singularly unfitted for any position of great authority, be it general or king.

Prince Hal may be an upper-class delinquent with a yen for petty criminality and hanging out in taverns with low-lives and thieves, but crucially, he has the capacity to change. There's not much evidence to suggest that Hotspur has similar capabilities. And so, on balance, one would have to conclude that Hotspur would not have made a better king than Prince Hal.

Compare and contrast Prince Hal and Hotspur in Henry IV, Part I.

Prince Hal is divided and complicated. He is the son of the king, but spends much time away from court. He spends time with common men, and, in Falstaff and his friends, with men of no honor. He is thoughtful where Hotspur is brash, and, as a result of his explorations, understands the complex nature of his society better.

By contrast, Henry Percy is "the king of honor." He is bold, poetic, daring. His spirit is fierce and runs hot. He's ready to challenge the world—in fact, he almost literally challenges the world, so long as he can gain honor, as you can see here:

By heavens, methinks it were an easy leap,
To pluck bright honor from the pale-fac'd moon,
Or dive into the bottom of the deep,
Where fathom-line could never touch the ground,
And pluck up drowned honor by the locks.
(I.iii.200-205).

Compare and contrast Falstaff with Hotspur.

Falstaff and Hotspur are two of the most memorable characters in the play, both larger than life. Both are knights, though Hotspur is brave and zealous, taking his vocation very seriously, while Falstaff cares nothing for the conventions of knighthood, being a coward and a glutton. The difference between them is underscored by Hotspur’s speaking in ceremonious blank verse, while Falstaff speaks in colorful prose.

The two knights represent extremes in every sense and are similar principally in being equally extreme in opposite directions. One of the most telling differences between them is shown in their attitudes to honor. To Hotspur, it is a sacred word. In his view, a knight ought to be prepared to go to any lengths to preserve or redeem his honor:

By heaven, methinks it were an easy leap,
To pluck bright honor from the pale-faced moon,
Or dive into the bottom of the deep,
Where fathom-line could never touch the ground,
And pluck up drowned honor by the locks;
So he that doth redeem her thence might wear
Without corrival, all her dignities...

Falstaff has a more practical and less idealist approach. He mocks the ideas of chivalry and honor, asking scornfully.

Honor hath no skill in surgery, then? No. What is honor? A word. What is in that word honor? What is that honor? Air. A trim reckoning! Who hath it? He that died o' Wednesday. Doth he feel it? No. Doth he hear it? No. 'Tis insensible, then. Yea, to the dead. But will it not live with the living? No. Why? Detraction will not suffer it. Therefore, I'll none of it. Honor is a mere scutcheon: and so ends my catechism.

These opposing attitudes to the essence of knighthood illustrate the yawning gulf between Hotspur and Falstaff in their attitudes to every aspect of life. The young Prince Henry, initially the boon companion of Falstaff in his drunken adventures, must steer a middle course between these extremes.

Compare and contrast Falstaff with Hotspur.

To some extent, Falstaff and Hotspur represent the twin dangers that Prince Hal must avoid if he is to become a wise, benevolent king. One of the most colorful characters in the whole of Shakespeare, Falstaff is an aging delinquent, a lover of wine, women, and song. Not only that, but he's mired in debt, throughly dishonest, greedy, and completely untrustworthy.

By comparison, Hotspur is almost a paragon of virtue. Though something of a firm, unbending moralist, Hotspur shares Falstaff's capacity for bluntness in his language and his interactions with others. Yet crucially he lacks Falstaff's good humor and bonhomie, which makes it difficult for him to impose himself on those around him. Unlike Falstaff, Hotspur takes life—and himself—very seriously indeed. He's fiercely ambitious and has no hesitation in joining his family's rebellion against Prince Hal. Hotspur is so single-minded in his pursuit of glory that he makes the fatal mistake of engaging with the future king of England in mortal combat. One certainly can't imagine Falstaff doing any such thing.

Either way, Prince Hal has been provided with an object lesson in the kind of qualities needed for a king. Once he accedes to the throne, King Henry V, as he'll then be, will combine Hotspur's raw courage and heroism with Falstaff's charisma and people skills to create a paradigm of kingship that will set the standard for centuries to come.