Looks like Simple Machines? Is it a vanilla install? If not, which mods?

I'm working on setting up a forum for a hobby site and I initially went to phpBB - but it requires mod installation just to keep spammers out, and compared to other packages I've used like WordPress, the process for installing mods for phpBB is pretty gross (I'ven't personally experienced it, but I've heard a lot of griping that updates, in particular, are brutal).

I basically want something that looks like the old GD.net forums from 2001, but has the backend ease of administration like WordPress. Does such a product exist?

I think it used to say it at the bottom. It's Invision Power Board.The forum at least, I don't know about the main page if you meant that.

Pretty much everything is Invision-based. They have a whole suite of products that we use

Have you tried Simple Machines yet? It isn't what is in use here at GDNet, but I suspect it will probably meet your needs, and it's a pretty solid forum platform -- the back-end isn't quite as clean as what WordPress provides by default, but the software also provides a lot of additional functionality -- if you do a quick search there are a number of sites where you can try live demo versions of forum software packages so that you can poke around the admin controls without having to go through installation.