Do you have a better link? I looked there and cannot find a forum that seems to have any different functionality than what we already have. I am specifically looking for a better search functionality and the ability to attach files. Yes, the current version has that ability, but only in it's most raw form. much needs to be corrected before I would allow uploads within the forum. There is no way I would allow forum uploads to "root".

I'm not sure about the search functionality but have you tried Active Forums?

http://www.snowcovered.com/snowcovered2/Default.aspx?tabid=242&PackageID=7305

May websites use this program.  I'm sure you can find more information about it with a simple google.

Personally I like the core forum module.  If you setup your folder permissions through File Manager correctly you can avoid many ( not all ) file upload issues.  Plus, since the code is available, I've made a few changes to help with my sites workflow.

If your site is indexed often by google you might be able to replace the native forum search with a google search.

I'd wait for the 4.4 release to see if that comes closer to meeting your requirements. 

The beauty of opensource is you can make it whatever you need.

Do you use Oracle?  Then try GoldFish.Net