Do yourself a favor and stay with XP until you get a new computer.
Don't think you are understanding what I was saying earlier about the AGP driver
, and you are confusing it with the video card driver, they are not the same thing. The AGP (also know as GART) driver is a motherboard chipset driver, and without it an AGP video card will not work properly if at all, or i your case allow the video card driver to even install. You will have the exact same problem with that 4670 for the same reasons you are having problems with your 9500.
That is also why I said that a new video card won't make any difference.
P.S. As far as a driver for your video card goes there is not now and won't be a Windows 7 specific driver for it, but there is a Vista driver, ATI Catalyst? Legacy Display Driver
that works with the cards listed, of which your 9500 Pro is one of.
Edit: To further the point, Help ON HD 4650 Graphics Card
that card is almost the same as the 4670, and it won't work in Windows 7 either.