I'm having a bit of trouble understanding you, Joni, but it seems that this is the situation:

1. Your son's computer stopped working and you decided that Windows XP was corrupted.
2. You installed Fedora Linux on both his computer and your own. It worked on yours, but his had problems with the keyboard and mouse.
3. His hard drive suddenly seems to be full and you can't back up.

It sound like something is wrong with the hardware, but from the information you've given us I don't know what it is. I'm sorry I can't be of more help.

Disregard the following, which is for the record!
@ onebuck
You can't check the MD5 for Fedora because they don't give you one. The installation disk contains the information and software to enable it to check itself immediately before the installer runs.

@ John
I've used Fedora since version 1 and I've never had anything break! It's true that it comes out every 6 months, but so does Ubuntu, which you recommend as an alternative. By the way, you don't need to SHOUT.