I wanted to change Windows7 Language from Hungarian to English. To do that I need to run Vistalizator. It can be run only with Admin Priviledge, which I don't have. It was successfully done.
The easiest way was using Parted Magic, which is a linux base distribution. If you don't have any knowledge about linux, normal windows repair would be easier.
Actually I did it in 3 ways on two machines.
It took time for each case. It would be not easy for beginners.