Regisrty clean: I would stick to CCleaner - some are a bit too invasive.
RE defragging, I use Auslogics Disk Defrag. Quicker than the MS one. Some say Defrggler is more thorough, but is slower. Maybe have both and run defraggler less often.
Firewall ; PC Tools
Anti virus: Avira
Anti Malware:1 SpywareBlaster (hopefully prevents)
2 Superantispyware (sometimes fids stuff missed by:
Together with CCleaner, all the above are free and I like them
Others will prefer Avast as anti virus, or MS Security Essentials.
I used to have AVG but recently it and Zone Alarm (firewall) seem to have a bit of negative press.
Dont forget only one anti virus at a time.