Running out of options....

Hi,
I am checking out a PC for somebody and it seems pretty messed up, even worst than mine was the last time. She doesnt know what she downloaded or what happened. All I know is I got a screaming call that its not working and she doesnt know what to do.

Anyway, I tried a few tricks I learnt here and nothing worked....here goes..

I am not able to START any utility software whatsoever....
download HJT... it installed ok but just wouldnt start...
download Spybot....it installed ok but wouldnt start either...
download superantispyware...it installed ok but like the others, it wouldnt start...
download malawarebyte's antimalware...it installed fine...it started to scan but like 2 minutes within the scan I got the blue screen of death and the pc rebooted...(tried it twice)
downloaded Avast antivirus...it ran but no difference after the scan...
I cant start in safe mode....after the drivers are initialized, it just stops..I have to power it down


Computer is a HP Pavilion Intel Centrino Mobile...1.7Ghz...2MB ram...Loaded with XP service pack 2

Sometimes the msg below comes up and sits on the screen and I am not able to close it out or access the desktop.
Warrning! Win32/adware.Virtumonde detected on the computer
Warning! Win32/privacyRemover.64 detected on your computer

Prior to this msg coming up, I was able to start up in normal mode and go to the desktop but with lots of virus warning fromt he antivirus. Now thi smessage just sits on the screen...wont move, cant get beyond it. When this happens, all I can do is power down the machine then reboot it and then it may start normally if I am lucky...otherwise, keep powering down and rebooting until it starts and goes to the desktop.

Any suggestions? How can I get around this ugly fella?

Hey dont sweat it, I had to reinstall. The pc was getting out of hand and I just did what I had to do.
Thanks anyway