Sounds rather like a malware problem, it would be worth trying to scan your computer using several different security scanners/sites. See Troubleshoot Firefox issues caused by malware

Hello John, many thanks for your support & taking a moment to answer my call for help. I'll check out your suggestion and maintain dialogue via this forum. Incidentally - the wonders of www incite me to say this, not knowing where the receiver is in cyberland - I'm a British expat' residing in outer Paris, France.

Cheers

Further to my above post, and with hindsight, I think my issue may originate from : http://lo.st/ It popped up recently and I may have clicked on it carelessly.

I have since installed a plug in, " NO Script" ...... http://noscript.net.

if anyone has any comments to make on this.

Many thanks

I am British, and could describe myself as an ex ex-pat, as I have previously spent a few years working abroad. Obviously sites need to make money, and some will quite aggressively flood you with adverts. Merely un-enabling javascript and if the site is not using video disabling FlashPlayer will often reduce some of the impact.

There is a constant battle between addblockers and advertisers. One recent comment about no script is this post

You should not normally however get popups and sites appearing from nowhere if your browser is dormant. Whatever you have seems to have overstepped the demarcation between advertising and malware.

I do not see any immediate indication that the site you mention is malicious.