Hey Debby,
I don't know how you are trying to load the Report Designer, but check out the link below for tips, videos, and a link to download the designer.
http://www.methodintegration.com/cs/blogs/methodblog/archive/2008/06/18/3-steps-to-becoming-a-report-guru.aspx
If you still cannot open it, try clearing your web browser cache. In Internet Explorer you can do this by clicking "Tools - Internet Options - Browser History". If you do not use IE, you can easily find out how to clear the cache by searching Google.
Please let us know if you are still having problems after you try that.