- ANY - of the ICSA Certified AV products (
https://www.icsalabs.com/icsa/icsahome.php ) will give suitable performance.
Many like free AV's from GriSoft (AVG) or Avast. Some prefer commercial
products such as McAfee, Norton, Nod 32 and the list goes on.
If you can install trial versions of some of them since beyond ICSA
certification it basically is a personal preference in regards to GUI used,
update methods, scheduled scans, ease of use and how well they play
on -your- machine.
Personally I use Norton Internet Security 2005 and for my machine and my
needs it works great.