I've also beaten Metroid Prime 1 on Normal/Veteran (AKA hard), MP2 on Normal (I forget if I did it on veteran), and MP3 on Normal/Veteran/Hypermode. The originals and the MPT equivalents, with all items (on MP1/3, not sure about 2). I've beaten Zero Mission and Fusion, though I'm not sure if I've done Zero Mission on Hard yet; both with less than 100% items. I've beaten Super Metroid once, no 100%. Don't get me started on the pinball game and the only ones I haven't beaten are the original and Metroid II... yep I'm a Metroid fan!
The most recent game I beat before Other M was probably Final Fantasy XII, which is EXTREMELY underrated (by hardcore fans anyways; the professional reviews are pretty accurate).
PS: Oh! I almost forgot, before FFXII I beat Strong Bad's Cool Game for Attractive People. Now that was a hilarious game!