I don't know much about gaming headsets but from the price range of the Creative HS-800 it doesn't seem like a high end headset and I don't think you would get that much of an improvement in sound from a new sound card.
Note: I'm not calling it a bad headset, just not high end.
The sound chips on motherboards these days are pretty good, for being built in. I wouldn't buy a sound card.
by "better wired" are you saying i should buy a better headset?