What can Windows XP command-line utility be used to find corrupted system files and restore them to the correct versions of your computers system files can become corrupted?

SFC.exe.

In windows XP, the system file check (sfc.exe) command line utility, with the scannow switch, locates and restores system files that are corrupted. This command protects files that are considered protected system files. If a file needs to be replaced, the system will require you to furnish the original from a file location or the installation cd.