Links Locking Up Page

In the posting area where you can make text to a link its graying out my whole screen for example I took a screen shot for you to vise https://www.nccsites.com/DROP/WPLINKS.jpg After clicking the Link button and my screen gets grayed out I can’t do anything till I navigate away from that page.

Im using a Mac with Safari 4 and a Studio Press theme I have tried it on 3 different themes on 3 different installs of Word Press and Im getting the same problem each time. The only thing That I can think that it may be causing it would be Safari 4 so Im going to go download Firefox now but if someone has an answer please let me know.