In case anyone else has made the mistake of upgrading to Internet Explorer 8 and is suffering from having the tabs randomly not connecting, I have the solution at last.
It is a conflict with AVG Anti-Virus and the Link Scanner option. I have now disabled link scanner and I have no further connection problems.
Having said that, I have now moved all my bookmarks over to Firefox and I have abandoned Internet Explorer 8 apart from a couple of websites that require IE8.
It is a shame that neither Microsoft or AVG could figure this out or even acknowledge the problem.