I knew I'd be ragged about the Firewall. Will try and download Zonealarm, if it will let me. The reason I don't think its IE is because IE was letting me download before I downloaded Avast.
Unfortunately I can't download Zone Alarm either. When I try the green progress line comes up at the bottom of the screen, takes about 10 seconds, and then nothing happens. Its probably something really simple, but I'm totally lost! have spent ages tying to adjust IE and Avast and still it doesn't work.