I'm freezing!

My 2 year old Packard Bell easynote was working absolutely fine till recently. I hadn't done anything to it but now the keyboard seems to be freezing the screen.It starts up fine & is ok if i just use the pointer/mouse but as soon as i press any key it freezes & nothing works - even control/alt/delete. I have to switch of by power button & restart.
Can't start up in safe mode as need to press the arrow key & it causes it to freeze again.
Using Windows XP, I have tried system restore, scan disk, defrag, full virus scan etc etc & they show no issues but problem still there - please help!