He could try reinstalling it and then try deleting it or perhaps he should look at the actual game file or indeed at what the CDROM says when inserted, some games have their own built in uninstaller which would probably work.
As another idea. I have had considerable success removing programs manually. If you goto where the main program is installed on the C drive, usually under Program Files and right click and delete it and then run Ccleaner it can search for leftover bits of programs. It should find the rest of the deleted program and then allow you to get completely clear of it. It has worked for me on several occassions including a corrupt program file on a friends computer just on Friday past. In his case it was AVG anti virus, it wouldn't let me delete it or reinstall it. I deleted the program manually as above, ran Ccleaner to get rid of the leftovers in the registry etc and then was able to reinstall from scratch and now its back working perfectly.