Sorcha: Probably everyone with a teenager in the house has the same problem. Teenagers like to download lots of freebies like file-sharing programs (Kazaa, etc.), instant-messaging programs, games, etc., many of which come bundled with nasty stuff that fills up your hard drive, crowds your memory, overloads your internet connection, slows down your computer, fills your screen with pop-up ads, takes you to websites you don't want to go to, and might even cause the whole system to hang occasionally. Some of the stuff even stays there after you think you've uninstalled it.

These problems are solvable, but you will need to learn more than you ever wanted to know about operating systems.