Operating system not loading

Hello, I lost all the data on my hard drive when my pc crashed reciently. The power supply had to be renewed and then I reloaded windows XP using the recovery disc, after 2 days of working ok the system shut down again. When I re booted it went through the normal system startup procedure then stopped before loading windows with an error message saying that a windows file was either missing or corrupt and could not load windows. Then suggested running the windows XP recovery disc to solve the problem, and press thr 'r' key on start up.
When i run the XP disc from boot up it stops before it gets to the 'r' command and I cannot reload windows.
Anyone got any sugestions? Also, would a new hard drive solve the problem? Is it corrupt/broken or is the operating system disk at fault. I have Norton Internet Security installed and this has not picked up any virus.