Urgent my mouse & keyboard not displaying

[gopikrish]

In my Win xp Pro I did system restore to a previous date and when I restarted my mouse and keyboard are not working. I mean no cursor is displayed. What can I do?
Actually I installed Microsoft Wireless keyboard and mouse yesterday but I think I specified system restore to 2 days back. Even I tried to put my old PS/2 keyboard and mouse but still its not working !
I dont have a Win XP Installation CD to do something. But I have net access since I am using old computer. So I can download Boot disk maybe?
Please help me. Thanks.

 

[gopikrish]

Hey i am getting Win xp CD. So can I reinstall Windows? Will it work then? Thanks.

 

[gopikrish]

damn the CD I got looks like its corrupted
Its 646 MB but no contents are there...
Tomorrow I will be getting the CD which was originally installed from the dealer from whom I bought the system...
I tried flashing the bios(i mean restarting or shorting it) but still same problem. I also tried taking away the battery and putting again and restarting but still...
I tried all possible ways like starting "safe mode" "previous best configuration" and also tried my old mouse+keyboard.
But is there any other way I can try?