Yes, lit24 sums it all up quite nicely.
The tension throughout the novel is one that is common to all of our lives; it is the inner struggle of believing that what we have been given in life is not enough, that we should always strive for something better and have great expectations of a more fulfilling future. What Pip eventually learns, after all he had hoped to gain and after all his endeavors for another, more rewarding existence, what he learns is the same lesson Dorothy learns in the Wizard of Oz: after all is said and done and hoped for and wished for, there is no place like home. And home is not so much a place as it is a state of mind, a way of being satisfied (ah, Satis House) with what one has.
In many ways, in the end Pip is back where he started in a simpler and less frought existence. It is certainly not by chance that his name is Pip: small and simple and the same in the end as it is in the beginning, the same read forwards as it is backwards: PiP.