Javascript Explorer 8 Windows XP

[ecchi]

OK this is driving me mad. My main machine is Windows XP with Explorer 8. It runs simple Javascript code and most Flash sites, however occasionally, mostly on Flash sites, I get a message telling me Javascript is disabled so my browser cannot access this site. I have tried changing every setting I can think of that may be causing this and updated everything I can think of, nothing works.

It is not a disaster because if I desperately need to visit such a site, I can boot up my Vista PC, but it is a pain because I use the XP machine 99% of the time (mostly because it is the lowest spec I expect my surfers to be using but also because I don't really like the way Vista runs).

Does anyone know if there is a setting I have not yet found that will allow me to run all Javascript on the computer, or an update I need to install? Google has not helped me, it only suggests things I have already tried.

Thanks.