Hmm, nice topic. The game that influenced me the most was probably Secret of Monkey Island (no surprise there perhaps
). The music, the ambiance and the graphics, all together in perfect harmony, not to mention the humour! I never before laughed my ass off playing a computer game, so this was a really unique feeling.
I still play MI1 & 2 at least once a year... can't stay away from the little buggers!
Some other games that really influenced me was Last Ninja, Commando and Pirates. I think I've wasted months of my life playing these games instead of going out doors. Mainly because of the gameplay but also much because of the great music within these games.