Your computer has been wiped clean and reinstalled. Your data was backed up as best as possible, and has been restored to your "My Documents" folder.
An extra account, named Limited User has been created. This user lacks the permission to install software. For additional security against viruses, use the Limited User instead of the owner's account.
The following have been installed:
Norton Antivirus - which came with your computer.
Firefox - this is a replacement for Internet Explorer, and tends to be a less popular target for virus attacks.
Microsoft Office - this was on there before.
A CD is provided with the following:
Drivers for your computer - they were downloaded from the manufacturer's website.
Several trials of anti-virus products, including Avira and ClamAV, which are free.
Your Norton anti-virus expires in 90 days, and you will either need to start paying for it, or purchase another antivirus program like Avira, Kaspersky, Trend PC-Cillin, or another program. (There's a new ad gimmick at http://www.trialpay.com/ where you can get "free" antivirus software by buying products you don't need, and getting on all the junk-mail lists.)