Keyboard typing weird things

HI....big prob, dont know whats happening. When i type d or f on the keyboard.....it comes up with ds or fs on the screen,, without me typing 's',, i can delete the s but its a big prob.... heres a typical sentence when im typing things:

the letters ds ands fs dsont work so it types weirds stufsfs

Ands i trieds unistalling dsriver ands reinstallling it but it didsnt work....