Remoc's trying to save you some pain, by suggesting you get of CA He's not suggesting that you run with no protection... just that maybe there are better programs out there & that some of those could be freeware.

It's up to you whether you use it or not, but there are suggestions that it's not that good... check out the links below for some examples.
PC World - Review of the Computer Associates CA Internet Security Suite Plus 2008 Antivirus and Security
CA Internet Security Suite 2007 Review - Not Enough Bang for your Buck
Security Suites 2008 - CA Internet Security Suite Plus 2008 - Full Review - Reviews by PC Magazine
Review: CA Internet Security Suite Plus 2008 - New Zealand's source for technology news on Stuff.co.nz

Are you making sure to scan all files that you download with your AV, before opening them? There are heaps of infected files being shared & you do have to be really careful. It's so easy to download a nasty.
* WARNING: Viruses on network you should be aware of ! *
If you're seeing popups (apart from Pro nags etc) then it might be wise to scan for spyware/adware.

It shouldn't matter whether you're using LW basic or Pro... both connect to the same network & neither have security features.

I appreciate being saved from pain, but I don't yet know the name of anything anything more efficient than CA.

Thanks for the tip about scanning downloaded files before opening - I've done this, admittedly using CA Virus Scan, and nothing detected.

However - I have downloaded some so called mp3s which appear ok, but when I click to open, they open Media Player with a message about extension does not match file format, then when I click the play button, it opens up two IE7 windows - a ****** [ < edit - these asterisks appeared where I typed the word C-A-S-I-N-O] .... and a Dating site - pretty dodgy - so if you know how to avoid that stuff, I'd be grateful.
What do you use to scan safely?

Cheers.

Everyone has their favourite programs, here's what I use:

Firewall: Comodo Firewall Pro The free one, not the 'Plus' version that you pay for.
AV: Avira AntiVir Personal The free one, not the 'Premium' paid version.
Malware prevention: SpywareBlaster (free)
Malware removal: Malwarebytes The free version.
And sometimes: Spybot S & D (free)

There are other freeware programs which a lot of people use...
Firewall
ZoneAlarm Firewall

AV
avast! antivirus Home Edition
AVG Antivirus Free Edition

Malware
a-squared Free
SUPERAntiSpyware
Ad-Aware Free 2008

Watch your search results & if anything looks weird (eg no info showing when you hover your cursor over the file, or just something like 'track 1' showing) then leave the file alone. If a file's less than 2000 KB - leave it alone. If a file has an extension type, in LW's 'Type' column that doesn't match what you're looking for (eg if you're looking for a music file but the search result shows as .exe or .zip) - leave it alone. Any file that has a description of .mp3.exe is a nasty.

Other links to help with crap appearing in search results:
Fake files showing up in search results

How to find music (tips for video also)

How to use Bitzi

You could also use this hostiles list & see whether that cuts down on spam: The TechNutopia Fullsize Hostiles List for BearShare and LimeWire