Tricky XP installation help

Here is my setup:

ide1 master=C drive windows 98 (system-according to disk management)
ide1 slave=D drive windows 2000 (boot-according to disk management)
ide2 master=storage drive
ide2 slave=dvdrom

My C drive is making a ticking noise (its 8 years old) and it sounds like its going to die. I want to replace that drive with a new one and install Windows XP on it.

How do I go about doing this without destroying my ability to access my win2k installion on the other drive. My C drive has all of those system files in its root directory (IO.SYS, ntldr,cmldr, boot.ini etc...)

Any help from you guys would be greatly appreciated.
Thanks, Jen.