cd & cd/dvdrw drives come and go

I've been having trouble similar to some of the posts I've read, but a little different. My cd drive has disappeared on numerous occasions, but eventually comes back. My dvd drive hasn't disappeared, but it does become just a cdrw. I have an HP Media Center, and HP help wants me to to a nondestructive system recovery, but I'm hesitant about that because some of my programs, ie Phone Tools, etc are not easy to reinstall as there is no cd. The last time my dvd changed to a cd drive, HP had me make changes to the registry and uninstall the drivers and this did work. However today, my dvd is again a cd drive. I tried just uninstalling the drivers and then having windows reinstall them, but when the dvd driver was reinstalled, windows named it a cd drive. I saw the post about running the sfc.exe, but I don't have one for xp. I did a search and found on in my back up file from my old computer, but it had ME so I didn't think it would work. Any suggestions as to where I can find the sfc.exe or any other troubleshooting ideas?

sfc, or system file check is included on all xp computers.
you need to go tostart/run and type in cmd and hit enter
it will bring you to a black box with a dos prompt
at that point you type in sfc /scannow
and hit enter
windows will start the file check

Welcome to Windrivers sylviad1

In addition to Geoscomp's suggestion there is a sticky thread at the top of the cd forum (Handy Stuff) Download and run the filter driver load order utility and post the results here.