If you want to both see the 'good' ending to this game, and retain your sanity, then do a Youtube search. This game will frustrate you, but it only makes it so much more rewarding when you finally work out and pull off the moves you need to rescue a bunch of Mudokons, the slaves trapped in Rupture Farms. The Gamespeak feature is still cool to this day, but I feel that it worked better with a Playstation controller - the buttons were easier to press without contorting your wrists. The visual style is incredibly unique, and it helps to emerge you in the experience, and possessing Sligs (armed slugs) and making them explode into meaty chunks never, ever gets old.
The game's hard, but every other game's just too easy. Go on, accept the challenge!