Windows 7 - win7 or pc issue

Hi All!
4-5 months ago I installed Windows 7 pro, 64 on my pc and it worked fine. then I didn't use my pc for 2 weeks and when I started using it again there was something really wrong with it.
If I try to type any numbers it will write one of the other characters instead, as if I used ctrl or Alt Gr. But pushing ctrl or Alt gr doesn't change the character. And the numerical part doesn't work at all.
Also the mouse behaves odd, sometimes it act as if ctrl was pushed as the same time, marking everything.

Its a plug and play desktop set (wireless -usb) so it has no drivers and works fine on other pc's. Also another desktop (wired-usb) and another mouse(ps2) behaves exactly the same on my pc so it nothing wrong with my keyboard and mouse.

So far I have:
Tried all 6 usb ports.
Went into the device manager where I disabeled and enabeled all usb ports.
Tried to update the drivers but it claims to already have the best ones installed.
Started in fail safe mode.
Plugged out, unstalled and restarted.
Checked the keyboard language settings.
According to the online keyboard in google the pc recognizes that i try to type a number (the number gets highlighted on the screen when I push the corresponding key on my keyboard) but despite that the pc will write another symbol.
Tried system restore.

Still the problem persists. I just don't know what to do more plz help.