yast2.....

Hi everybody, This is my first time here and see how effective is. I just want to know how to use yast2 so that I could switch or change from operate system and both should still on or active. I have win and linux 7.3 on the same harddrive. I'm working at an internet caffe. If clients don't have idea about linux then I just want to get the win OS without re-start and put linux back when that client is gone.