Can't Boot in Safe Mode/Task Manager Blocked By Administrator

Ok I am currently using my brothers computer that he built by ordering piece by piece, so this may be diffictult to explain it, but the computer is running Windows XP


I managed to contract some virus of some sort. The first symptoms were pop ups of porntube.com, then the generic box of You have a virus download software now. I tried to get AVG to scan but it could not detect anything, and by the time it was done scanning the screen was filled with download antivirus screens, and porn pop ups.

So i restarted my computer, and tried to start it up in safe mode, but as soon as it loads all the drivers it forces a restart, I then tried to start safe mode with command prompt and network, but agian the same thing.

So I then tried to start the computer normally, this actually booted up into windows, I saw my desktop and a flash of the toolbar then everything dissapears but my background and nothing happens, when i try to reboot and hit ctrl alt dlt as soon as i see the desktop i get a message saying task manager is blocked by administrator. This is my home computer and there has never been an issue with task manager before.


The only other thing I can think to do is the Windows XP disk, and try something with that, unfortunetly it is currently misplaced and I think it might be in another city right now. Is there anything I can do outside of using the XP disk, and if I do in fact have to re-buy the XP disk (which actually will only be like 10 bucks due to the sweet deal microsoft has with IU) what will need to be done?


I would really like to try and fix this by the weekend with school and papers etc. So I hope I provided ample information and someone out there can help me.

Cheers,
Mac

 

thanks for the advice,

I was able to buy a new windows XP cd and reinstalled windows which seemed to take care of most of it, then downloaded a Malware removal device to clean up the rest.

I now have to reinstall drivers and such, and lost a few documents but luckly i had most of my documents stored elsewhere due to it deleated everything in my windows folder, including my documents

But yes thanks again for the help