First thing I would do is download Firefox and see if you have the same problem. You may still have the same problem, but that would eliminate the browser as the problem. It's always good to have multiple browsers to help trouble shoot a problem like this anyway.
And at some point I would upgrade to IE8, but maybe wait until you get the mail problem solved. Some times it's better not to introduce too many variables all at once to help identify the problem.
Sarari would bee just as good. Why not download both.