1's pretty general (Morphgear emulates 8 completely different systems!). But mine would have to be every Sonic game, every Mario, every Castlevania game, every Bomberman game, every Final Fantasy, hell every Squaresoft game, every Enix game, every Phantasy Star game, almost every Capcom game, and every SNK game. Also a TON of stand-alone games that I won't even begin to list.
2's illegal provided no one considers any freeware games as their favorites.
For 3, I think if you un-hi-res-aware Morphgear you can make it very playable on GAPI mode with Picard's GAPIQVGA tweak. I don't know, try it out. Information on how to do so can be found .