I'm very new to DotNetNuke and when I first started using it, I was adminsitering it with Firefox 3 beta. I found there were a number of errors like when i was usign fckeditor, I would click to create a link or insert an image, a new window would pop open and then nothing would appear in that new window. 

I was trying out the File Manager and I clicked on the + sign next to the root directory. A little spinning circle appeared and then nothing happened for a long time.

After that I began to adminsiter my site with IE 7 and all the problems were resolved. I realize that it's a beta version of Firefox, but I just wanted to bring it to the attention of those people here who might care about that.

Nick