Is it ok if not everything I list is movies?
Ok, movies I'd like to have experienced are:
Starship Troopers - as Juan Rico (either the movie or book version)
StarWars Episode II - as Anakin Skywalker
Do anime movies count?
Battle Angel Alita - as Gally herself or Ido (theatrical version of a really awesome graphic novel)
Non-movie stuff I'd like to experience for real:
HALO - as the MasterChief (X-Box video game)
StarCraft/StarCraft: Broodwars - as any marine (computer video game)
but the two that top my list are:
Xenogears - as Fei or Citan (Playstation/SNES RPG)
Outlaw Star - as Gene Starwind (the greatest anime of all time, aside from Neon Genesis Evangelion)