I would definitely go with Op.2, No.1, in F minor. Perfect for your level.Phil
op 14/2 in G
This is a good one, and not played often, but it may be a little too easy. I still stand by Op.2, No.1. Phil
Go after an opus 49 or an opus 14. I don't care if the notes look too easy for you. Beethoven's pianism isn't something to jump right into, and if you have the time it's always best to do one of the 'easier' sonatas first.
Maybe look at the Sonatinas, or you could always go with the very popular Moonlight Sonata.