XP has SERIOUS win32 problem

[vinny_g]

A friend of mine sure has major signs of PC virus infection on his latop. Every time he logs in the pc mentions that something is wrong with his firewall but once clicked on it says "PLEASE CHOOSE THE PROGRAM YOU WANT TO USE TO OPEN THIS FILE" and say "FILE: RUNDLL32.exe" with the list of applications i can use to open.

This happpens for EVERY application i try to open which is VERY annoying. User account cannot be accessed (an error window pops up for that one). It had AVAST 4.8 Professional installed which i've used to thouroughly scan the system to try to fix the problem but....STILL currently here.

I've tried re-installing windows XP by CD but.... it wont boot up at start up and wont install when pc is on. I'm running out of options, i've tried just about all i know, which i guess isn't very much about this situation.


WHAT IS THE PROBLEM AND HOW CAN I FIX IT.
Thanks for reading my concerns and for your answers!