Is the ending of "Pride and Prejudice" fairytailish? Why or why not?
In a lot of ways, it is. Most romantic movies end in a marriage, as do a lot of fairy tales. So in the sense that the story ends in a marriage with a "happily ever after" feel to it, yes, it is a bit "fairytailish". The fairy tales and movies tend not to go beyond the marriage vows. How are Darcy and Elizabeth going to be together in married life? Did they really know each other that well? How are their two VERY different families going to mesh? The story doesn't answer this; it just focuses on the love of the characters overcoming obstacles-very fairy tale. And if there is a "wicked stepmother" character it could easily be embodied by the charming but insidious Wickham, who threatens Elizabeth's happiness in several ways, or the more suited Lady Catherine De Bourgh who tries to forcibly keep Lizzy and Darcy apart.
The story is NOT fairy-tale-esque in the sense that there are many other characters who do not find felicity in marriage. Take Charlotte for example, marrying the absurd Collins for practicality's sake. Take Wickham and Lydia for example, who will probably drive each other insane in a year's time. Austen doesn't just show the perfectly happy, she shows a spectrum of possible scenarios.