Korean Version of XP (OS) installed with English XP

I have 10 PCs that have XP Pro SP 1. Recently we started having Korean computer basic classes. The instructors friend came by and installed the Korean version. Before this I had no problems and had updated to service pack 3. Now you can not access internet explorer from the icons and the service packs have been brought back to 1. The computer freezes a lot, but the Korean version runs smooth with no problems. I can not see where he installed from the partitions.

Can someone please tell me what I should do?