The fact that you can get on them means it is sort of working but the fact that you can't then use the functions means there is something screwing with the top layer.
usually it will be a scripting problem with the current version of the various web front ends and you running on an old version which the website isn't designed to support. Which is why I suggested making sure you had java updated.
As a quick fix try downloading firefox or google chrome and see if it works on that.
Also as well make sure you have the service packs etc up to date on the OS.