Hi
the first bip is BIOS telling you post is fine but when it goes to boot widows their a problem with your drive
1- put in windows cd and try to repair it
2- let it boot and then press r (assuming your with xp)
3- choose your windows (likely 1) - put oyur admin passowrd
4- type in chkdsk /f /r and let it run
5- if it fails you might have to reinstall windows or your HD might of fail.
You can also download a ISO windows boot cd to see if you can save your files before reinstalling / changing HD
Good luck