Win ME boot problems

A friend of mine has a problem booting to windows the system stops at the Win ME boot screen and wont go no ferther. system is a dell 4300. I have not tryed safe mode het but I dont have a clue what the problem could be except bad hardware or corrupt system files or a virus. ? If I can startup in safe mode can I burn CD-R's to back up files so I can reinstall the OS. The OS has been installed for a few years.