>>>To tell you the truth - I haven't been on my home pc yet - too fed up with a day of work at it. I'm storing up all the suggestions till I can try them one after the other. I'll certainly let yez know the results>>
>
>Are you using Windows XP? How about using System Restore? You can restore your PC state from previous date, provided system restore is not turned off. Then to ward off this Pop ups, you can use ZoneAlarm Pro firewall, quite effective. Im using also Spy Bot (free ware), and Pest Patrol for my anti-spyware.

Thanks Jojo. I'd considered restoring. Thanks for the heads-up on Spy Bot.