A search for anything involving Beethoven will yield an enormous amount of hits, so it's tough to nail down exactly what you want. Luckily, you've narrowed it down to his piano works. Beethoven was an ace piano player and was known for his ability to improvise on the spot, so any interpretation of his piano works must be approached carefully and with great respect. In my mind, no one has done this as well as Richard Goode. Mr. Goode has dedicated the majority of his musical life to the interpretations of Beethoven's piano music, and he was the first American to record the complete Beethoven Sonatas. His works are very highly regarded by "the experts" and if you're looking for a place to start, these might bear further exploration.
The Sonatas
Beethoven: The Complete Piano Sonatas / Richard Goode - Nonesuch - NON 79328 - - HBDirect Classical
The Concertos
Beethoven: Piano Concertos / Fischer, Goode, Budapest, Festival Orchestra - Non - HBDirect Classical