something like this would do you http://www.ebuyer.com/UK/product/111198/rb/26268320811

You said your new board isnt AGP so im guessing its pci- express? if so the above will work fine, should run vista fine and you can play the odd game, dont expect high graphics settings but it will be alright

P.s GT and GTX are the best name tags to look for, LS LE are basic entry level items