I'm sorry, it took me a few minutes to write all the solutions. Please try each of the followings until it works:
1. Try with blank password (don't enter any password.)
For solutions # XXXXX to # XXXXX below, please see full details at the website below:
2. Click on Start -> All programs -> HP Tools -> HP PC System Recovery... ,etc.
3. Turn off the computer, then turn it back on, then right away, keep pressing & releasing the key F10 quickly and repeatedly to see if a recovery / restore menu appears; if yes, then do a factory restore/recovery. If needed, try with F11 key instead.
4. Insert the first recovery disk, then turn off the computer, then turn it back on, the press the Esc key quickly and repeatedly until the boot menu appear. Then use the Up and Down arrow keys to select the cd/dvd drive model, then press the Enter key, then when prompted, press the Enter key again to boot from the cd/dvd... drive. (You want to start the recovery disk right after turning on the computer, like in the image below; click on the image below to see. You don't start the recovery disk from windows.)
5. Turn off your computer. Then turn it on, and right after the black screen with white text or the computer company logo disappears, press & release key F8 repeatedly until a menu appears, then you select Safe Mode (note: if there is no menu, then try the same steps again, but this time, press key F8 a bit earlier). Then login with the Administrator account if available (or type Administrator and leave the password XXXXX). Then go to Start->Control Panel->User Accounts, (Manage another account), and reset any (admin) account password XXXXX
Please let me know if you are stuck at any step.
Edit: It looks like you are away. When you are available, please click on the Reply to Expert tab below, and reply back to me, so I can help further if there is still any issue. Thank you,