Did you see this sticky thread:
http://www.gnutellaforums.com/showth...threadid=49809
First check this.
I am not sure when the Safari Browser was introduced, Nor am I very good on 10.2.8, but if you downloaded using Internet Explorer something like this might happen on later OSX versions. Safari Opera and Firefox will download the file properly, and it should be a dmg file. so try a change in browser if applicable.