1. How are they set up ? Guest ? User ? what are thier rights ?
2. When you "deleted" IE you might have done it from the "All Users" under Documents and Settings. In this folder you can set up what everyone see's (GLOBAL) on your PC.
3. If you want indiviual people to see certain things you need to make sure that the Rights (right click- Properties) on that folder is set to you only.

Each person can be assigned rights to the folders that you want them to see. Make sure that when you do this though that you do not restrict yourself on the folders and make sure that you are careful when doing this. Its easy to get carried away Happy

Hope this helps.