Jaremu

Hello everybody, I'm in kind of trouble, you see, I was installing few days ago Windows 98 SE on my grandma's computer, and just got an idea "Okay, so let's install this auto-pacher, this should be good thing". But. The problem is, I just installed wrong language (english - should be polish, silly me), and this is somehow troublesome for her... so then, is there any solution, how to get back to my oryginal language version of OS (polish)? Maybe, which files i should replace, or something? Somebody help please? I will be very, very grateful.