Well, the windows interface should definitely be one of the options, because its true that for most computer users it is the only interface they've ever worked with. Although I really doubt that Uncle Bob will go through the trouble of installing ReactOS to make his computer a little faster, if the only thing he uses it for is word processing and web browsing. And while Uncle Bob may prefer a windows interface, i don't think that he is the target market here. I think that most people switching to ReactOS, once its in a solid state, will be more experienced computer users, capable of figuring out how to start a web browser even if the interface doesn't necessarily have a microsoft start menu. That's just my oppinion though. Personally, I would switch to ReactOS because it makes me feel good not to use microsoft products. That's why I switched to linux. But if i can use all my favourite windows apps, games, and drivers on an open-source system, I might use that as well. I kinda see ReactOS vs. Windows as Firefox vs. IE. But maybe that's wrong.
So about porting other desktops to ReactOS, how would that work? what kinds of desktop alternatives are out there? I mean, I know of Object Desktop by Stardock, but that costs 50 bucks... and as far as i know, the open source environments like KDE and GNOME don't really work with windows (correct me if i'm wrong?)
And if anybody is interested, I have some ideas for an interface that would be different from windows, but still very easy to figure out, even for someone like uncle Bob. Maybe i'll sketch a draft and post it here sometime.