possible keyboard problem

Hi everyone Im back with another problem jeje.

Welll my problem is that in Christmas my parents gave me FIFA 08 for my pc, but at the moment I installed it, everything moved by utself, I mean, I wasnt pressing any button and the menu directionals moved down and down and I wasnt pressing any button, and at the time of playing, the players moved by themselves, so I uninstalled it and installed it again and the same problem continued, ss I went to return the game a day after. But yesterday my uncle gave me this king kong game and the same problem ocurred, when I started played the character starting moving and I wasnt pressing any button. So, what can I do?

no i dont eat at my computer and this problem occurs on my fifa 08, and on my king kong game, but for exaple it doesnt happen on my warcraft games