Try to run "chckdsk x: /f", without the quotemarks and where x is the drive. I think you have to do it in Safe Mode MSdos [restart, press F8, go for "safe-mode with command prompt"], or when in XP mode: right-click on drive X, open Properties, Tools-tab, click "check now". You'll get message is not possible, only after restart: it will be scheduled at next reboot - just reboot.
If your disk is just too old, funked-up, or qurwalized and you just want to try to save the data, then please do use special software (or some PC-freak near u) - don't let XP try to fix it! For