The choices in the beginning impact the order in which you receive abilities.
Abilities are things like additional combo hits, different combo strings, special moves, etc.
But if I'm being honest, if you LOATHE the gameplay, it's never going to really change much (other than you getting cooler moves), and if you don't like Disney, you're probably not the right audience for it.
On the other hand, you might like KH2 more, the combat is much better. Or Birth by Sleep.
All that said, the later-game environments are pretty fantastic, so it might be worth playing through just to see them :)