Although you could try booting to Safe Mode, then use System Restore again, I'll guess it may not work well for you.
HP/Compaq should have a hidden recovery partition on that computer which will reformat the drive and reinstall the operating system, all drivers, and all software back to its original factory state. (If you have recovery discs, they should do the same thing.) You'll lose all the files you haven't backed up, but it should get the computer running.. On HP/Compaq computers, accessing the recovery partition usually involves pressing the F11, or F10 key immediately after starting the computer.. See the instructions in the link below for using the "System Recovery" or "Factory Reset" in the Recovery Manager options.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c02638587&tmp_task=useCategory&cc=us&dlc=en&lang=en&lc=en&product=3878189#N41
Hope this helps.
Grif
I run XP on a Compaq CQ60 Laptop. It was running really slow and freezing on some pages after doing updates. So I done a system restore which went slower than ever. Then when it rebooted it frooze. I turned it off and tried again. It comes up with the first page of choices of rebooting. Then a blank screen. Can anyone help me please???

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