To be honest there are loads of different Anti-spyware, anti-virus programs out there alot are free and alot are expensive.
If you think your computer is infected you can try multiple programs to help you rid the pesky bastards.
FREE PROGRAMS
Anti-Spyware
Spybot Search & Destroy -
http://fileforum.betanews.com/download/Spybot_Search_and_Destroy/1043809773/1
Adaware Personal SE -
http://www.download.com/Ad-Aware-SE...045910.html?part=dl-ad-aware&subj=dl&tag=top5
Windows Defender (You need to have a valid copy of Windows XP)
http://www.microsoft.com/downloads/...E7-DA2B-4A6A-AFA4-F7F14E605A0D&displaylang=en
Anti-Virus
The one and only in my eyes worth using
http://free.grisoft.com/doc/5390/lng/us/tpl/v5#avg-free
PAY PROGRAMS
Anti-Spyware
Spyware Doctor - (This will rid anything Spyware wise I have never once come across something it couldnt get rid of) -
http://www.pctools.com/spyware-doctor/
Anti-Spyware
Symantec Anti-Virus - Definately the best if you want to buy a anti-virus package - you can buy it pretty much at any PC shop.
Other Tips
1. Make sure you have your Windows Firewall Turned On (If applicable)
2. If you have a Router, LiveBox or Configurable Modem ensure you have the firewall set as high as possible.
3. Always check to ensure you Anti-spyware and Anti-virus is up to date.
4. Run regular scans
5. Keep away from dodgy sites and never download anything your unsure about and dont say "Accept" or "Yes" to anything that pops up unless your are 100% sure its safe.
6. Any programs you download that say they are Spyware free be sure they are some have stuff like MyWebSearch toolbars that install which is highly annoying.
7. NEVER, EVER Use any peer2peer programs such as Limewire, E-mule, Soulseeker etc because they are all full to the brim of shite!!
8. Always be aware of attachments via e-mail make sure you know what your opening.
Thats pretty much it!