Some websites don't allow you to copy content from them. When you put your mouse on the page you can't select anything. There are two ways around this.

You can view the source of the page and then copy the text from there. In Firefox you can view the source by going to View > Page Source and in IE you can go to View > Source. Once you are viewing the source, you can copy to your hearts content.

If you want something slicker, you can overwrite the javascript that the site is using to block you from copying content. Once you are on the site go to the address bar and enter the following: javascript:void(document.onselectstart=null)

Once you enter it, hit the Enter key. You'll then be able to copy from the web page.