I moved the thread to Linux - Hardware, because I think that the hardware part will be harder to solve.
Do you use NTFS with XP? If yes, it's common problem with RH - it doesn't have NTFS supoort build in. But you can correct it easily - download the driver from
http://linux-ntfs.sourceforge.net/info/redhat.html. It should be rather easy - just read the instructions. If unsure, feel free to ask.
Hardware part: could you write more about your hardware? It'll help others to find drivers or just tell you how to configure everything properly.