This is where I see machines show issues, then eventually too many other problems appear. Maybe you have a restore CD?

If so, the use of SFC /SCANNOW is usable and you give it that CD when prompted. If not, you must complain bitterly to the machine supplier since your install and as delivered is not proper.

You should be able to use the add/remove software tool, the windows components tab to remove, then add the tool that is missing.

http://www.google.com/search?&q=xp+sticky+keys+registry is a GOOGLE that shows alternative methods, but I am concerned you won't be running XP (at least the one you have installed) very long.

Bob