Hey H@t Trick! Your reluctance to accept Vista with open arms is entirely understandable, however, I'd venture the opinion it's not
as bad as all that.
re. The Vista Start Menu:
This is my single
favourite part of Vista, especially when it comes to helping less experienced family members. Whereas in XP and before you either needed a really good memory or could be bothered to keep the Start-Menu tidy, otherwise it would become steadily more difficult to locate anything. In Vista, if you want Notepad (for instance) you simply press the Windows key, type 'Notepad' (although on mine I only need get as far as 'Notep') and hit Enter, and up it comes. I think this is much easier than hunting through the menu for something.
re. Explorer:
It is a little weird, having the address bar so high up the window, but it's easily gotten used to. I assume you've switched to 'Use Windows Classic Folders' to keep the Menu bar visible? The new address bar style can be changed under Folder Options too.
I haven't seen much in the way of free Vista -> XP Themes; I think this one looks quite good
http://www.stardock.com/products/windowblinds/wb55/index.14.jpg but it's for WindowBlinds, which costs US$19.99. Not a fortune, but not free, and even then it doesn't resolve the explorer window layout you dislike. It's a bit tricky, since most Vista themes are designed to take advantage of Aero, and most people seem to be trying to turn XP into Vista, rather than vice-versa.
I do honestly think that, while it's difficult to emulate XP's look in Vista, Vista can be tweaked in many ways to make it
at least as easy to use as XP. And some changes, like the Start-menu search box, I genuinely think are useful improvements.