Mozilla Crashed and IE is not working properly!

Ok, so my mozilla firefox crashed, and I tried to use ie to just simply redownload it, but everytime I try to download something or click a link, ie keep saying "Application not found". :confused I can't even click home, because it happens again. I really use firefox, so I havent used ie in a while. But if you guys could help me it would be a great help. Thanx.

BTW: I just tried to click the "[More]" link to look at the different smilies and it did it again!