No C: drive, just an E: drive. Can I safely rename?

Hello all.

I am not even a whisper of a geek, but I lurk here constantly, gleaning from the advice you all kindly give to others. I am responsible for maintaining our three computers, but I know just enough to get myself into trouble. I have never post here before because I don't know enough to offer help, and I have been able to get enough help for myself from searching existing posts. I'm stuck this time though and I hope I have post this in the correct forum.

My hard drive crashed last week. I finally decided that it was dead and moved my slave drive to master. I already had Windows XP Professional installed on the slave and had a backup copy of my original C: drive. It is up and running now in Windows XP. (Had a blast calling Microsoft to activate. rolleyes) I did restore from backup.

My problem is that My Computer shows there is no C: drive. Only an E: drive. I wouldn't care except that none of my programs will open up, although they are all showing in My Computer. All I get are error messages. Can I rename my E: drive?

I did find a Microsoft support page: http://support.microsoft.com/kb/223188/en-us?FR=1&PA=1&SD=HSCH titled "How to Restore the System/Boot Drive Letter in Windows." There are some warnings in there however that stopped me because I don't have enough knowledge and experience. It warns to only use this "to recover from a drive letter change, not to change an existing computer drive to something else." As I recall, in my old set-up, this drive was listed as the E: drive, after the CD drive which was the D: drive. I didn't worry about that, but maybe I should have?

Any ideas would be greatly appreciated.