CCleaner is a freeware system optimization, privacy and cleaning tool. It removes unused files from your system - allowing Windows to run faster and freeing up valuable hard disk space. It also cleans traces of your online activities such as your Internet history. Additionally it contains a fully featured registry cleaner. But the best part is that it's fast

(normally taking less than a second to run) and contains NO Spyware or Adware! :) http://www.ccleaner.com/

Defraggler. It differs from other defrag tools on the market, by enabling you to quickly and simply defrag the files you want to, without having to process the whole drive. Simply run it, select the file and defragment in seconds. No more struggling with the Windows defragmentation tool! http://www.defraggler.com/

Firefox . The Firefox Web Browser is the faster, more secure, and fully customizable way to surf the web. www.mozilla.com

Opera gives you the full Web experience everywhere. www.opera.com

a-squared Free 4.0 . Scans your computer for malicious software (Malware), including Trojan Horses, Dialers, Worms, Spyware, and Adware. A-squared Free is specialized in finding and removing them securely. The disk scan checks all files on your system disks for Malware. The scanner scans for Spyware Traces. Currently more than 1.2 million different types of Malware may be detected and removed.

homepage / http://www.emsisoft.com/en/software/free/ download page / http://download.cnet.com/A-squared-Free/3000-2239_4-10262215.html

There is lots at majorgeeks.com

Avira AntiVir Personal - FREE Antivirus Basic protection Protects your computer against dangerous viruses, worms, Trojans and costly dialers. New: Basic Anti-Spyware. http://www.free-av.com/

i know mate but want ppl to post stuff they use/used and would recommend to others