Computer won't boot even in safe mode!?

When I switch on my computer (infact its a friends whose I am repairing) it loads as normal until it gets to the GUI stage of Windows XP where it hangs on the screen which is light blue with the darker borders at the top and bottom of the screen. It does the same is safe mode and even when you select last know good configuration. Tried all options from F8 menu. BTW it is an acer aspire computer with an OEM version of windows installed with no disk. To make matters worse the eRecovery tool managment program won't load as it should by pressing Alt+F10 at POST BIOS screen, why would this be?