I think 88keys has a point in that - the Op.2 Sonatas are not really close to the five hardest ones; ok, number three's a little tricky, but not that difficult.
In terms of expression, the last sonatas are certainly the most demanding; but technically, in my view, the 'Hammerklavier' sonata is his opus primus.
But, just to tell you, I was looking for a way to get around Nr.2 myself when I was younger..didn't find it, but - well..
Good luck with the Sonata.
Regards