Microsoft has a pretty good feature comparison list to show you what comes with each edition... take a look and see what you will use and what you won't. Basic doesn't come with Aero or Media Center.. both of which I like.. but look and see what you'll use and what you won't.

There isn't any technical issue with Vista 64 Home Basic for multiboxing, the only real limitation I could think of is dual-CPU support is only available in the higher editions (they all support multi-core, though, afaik).