installed avast not rebooting now

need help, I installed avast with another virus scan installed by accident.
now i cant get to the bios screen so i can go into safe mode.
Bios stalles at the verifying pool data. I have rebooted several times and get the same issue. I tried pressing f8 over and over to no avail.
Before BIOS i get the 1st motherboard screen with ctrl options but not sure what to do on that.

urgent help please :-[ :-\ :cry:

Can’t you boot at all? I mean, can’t you pass from the BIOS checkup? If so, maybe there is another problem because you’re not being able even to start Windows.
But with F8, can’t you use the ‘last known good configuration’ option?
Which was the other antivirus? I bet on Norton…

no boot.
it stops in the middle
I can’t remember the other virus protection I believe it started with an s.
It gets on the page-
PCI Device Listing: then it list some stuff and continues to the Verifying DMI pool data with a little blinky thing continuously blinking(almost like it is thinking about it)
I have had that screen everytime i reboot (more than 6 times).
no F8 key function

Maybe the only solution would be overinstallation. You can solve the problem and you won’t lose your programs, settings, data, files, etc. Just choose ‘Repair’ installation of Windows and install ‘over’ the old installation.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;315341
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q314058
http://www.webtree.ca/windowsxp/repair_xp.htm