Windows XP Error Help!!!

My roommate's McAfee expired so she installed Kaspersky Internet Security ver. 7.0 on her PC. Now the PC gives the following Error:

"Alert! OS Install Mode enabled. Amount of available memory limited to 256MB. Strike the F1 key to continue, F2 to run the setup utility"

When I press F1 Windows loads to the Windows User account screen. When I chose the User account that is the administrator for the computer the background picture loads and NOTHING else loads.

HELP!!!

 

did roommate uninstall mcafee before installing the new scanner?

 

She said No. But I have gone in the registry and taken out any entries I have found of the new software thinking that the new software was the problem since it didn't start happening until after she installed it. The only way I can get into anything is by booting the pc in safe mode and going into the admin account. And even then it doesn't load anything I have to do a Crtl-Alt-Del to be able to get the task manager to come up and I have to start a new task.

 

in safe mode try "Last known good configuration" if that don't work then its a windows repair using the xp install disk when options are showing its "R" to repair windows directory

 

http://support.microsoft.com/kb/307545

this microsoft help file to restore xp