it's a wierd happening, but sometimes when I hit a modifer key (ie. ctrl, alt, shift) I can only hit a couple other keys. so when I'm playing a game, say I'm holding ctrl and w. and I want to add a to the list so I'm doing ctrl+w+a it works fine, but when I do ctrl+w+s the system just beeps at me, what I can I do?

Clean your keyboard maybe? Just pry open the key that's giving you trouble, clean out any junk in there, and then pop the key back in. It's a start if anything.

It's possible that another program running, or the operating system itself is polling for that particular key combination, and due to the circumstances (you playing a game) - it cannot fulfill the request made upon that keystroke.

I doubt a messy keyboard is to blame, but who knows.