In the google search rankings, my forum's homepage shows up 4 different ways:
1. Points to the root name (eg example.com)
2. Points to forum.htm (eg example.com/forum.htm)
3. Points to index.forum (eg example.com/index.forum)
4. Points to index.htm (eg example.com/index.htm)

All four of these pages are the exact same (duplicate) content.

Is there a way to fix this so that google only points to the root folder? I think that the issue is decreasing my standing in search results.

Hmm?
you got me on that one?

But hey at least it is showing up in a google search. there are a lot of peoples forums that dont even come up,

The whole thing is hard to explain. for google search it has to do with how may hits the site may get,activity and the bots gathering information to be places in google's search engine.

But as far as you initial question.. I just dunno? you may want to try to contact google and ask them unless someone else knows here.

If anyone dose know please do reply.

There is a canonical link tag that search engines use to figure out that multiple pages are supposed to point to one page. This usually goes into the HEAD tag but it can be placed in the body. You put the tag on the duplicate pages and point them to the page that you want the search engine to pick up. The search engine will combine the page rankings for these pages. I put the tag into the welcome message for the index page.

Example:
<link rel="canonical" href="http://www.example.com/index.htm" />

The above tag combines example.com, example.com/index.htm, example.com/forum.index, and example.com/index.forum as one result.

Do not put this into a widget that is on every page since it will cause the search engine to have issues with indexing. Only use it on your main index page.