For some strange reason my keyboard works on bios, and there's no problem when booting. but as soon is time to enter the password on windows it will not type or let me put caplock or anything...That's the opposite of what we usually get!

What kind of keyboard? USB or PS/2 or wireless?

What operating system are you using?Is a PS/2 regular keyboard, and i'm using windows xp sp2
okay, so you have never used a USB keyboard with your MACHINE?

I sense corrupted keyboard drivers It's a long shot, but boot to "Safe Mode" and see if keyboard works there.If you've never successfully booted Windows in normal mode (and logged in) since the problem appeared, try starting using the "LAST known good configuration".

Tap the F8 key (about once per second or quicker) during system startup to ACCESS the Windows Advanced Options Menu. Using the arrow keys of the keyboard, select ITEM "Last known good configuration", followed by the Enter key. Windows should start with the configuration (registry?) of the last successful login.

Using Safe Mode to successfully login does not overwrite the "Last known good configuration". So you can attempt/use Safe Mode without losing the ABILITY to fall back to the "Last known good configuration" of a normal boot.