Some of my top picks for best free software
"AVG Anti Virus" by Grisoft
"Nero 9 Free" Free Burn CD's and DVD's
"CCleaner" from Piriform cleans cookies, temp, files, privacy entries, registry
"Comodo Internet Security" All in one Anti-Virus Anti-Malware Firewall and HIPS
"Comodo Backup" Automated backup utility light and fast
"Comodo System Cleaner" registry, privacy,disc cleaner and more
"LogMeIn Free" Remote PC access
"Malwarebytes Anti-Malware" removes all kinds of malware
"Opera Web browser" has built in bit torrent client and inline spell check plus a mail client
"Defraggler" from Piriform can perform scheduled defrags
"Super AntiSpyware" removes Trojans and many forms of Malware plus has alot
of other helpful tools to repair issues left over from infection
"Spybot Search & Destroy" by PEPIMK Software Malware remover with
Immunizations against infection and bad website blocker
"uTorrent" bit torrent downloader
"Fastone Image Resizer" resize and convert image file formats