If you’ve never ever worked with film before, you should without a doubt get a 35mm manual SLR with 50mm lens. Most of them look something like this:

I say this because they are perfect for helping people new to film understand how cameras work, how film works, and how to take better photos. It forces you to learn about ISO/ASA, shutter speed, and focusing. [Since most people these days are used to auto-focus digital cameras, focusing really is something that needs to be learned.]
When it comes to what brand of camera you should buy, it’s really all personal preference. I personally love my Canon F-1 and AE-1 better than any other camera, and other people love their Nikon, Pentax, Minolta or Konica the best. I think the best way you can really tell what brand you prefer is by shooting with multiple cameras, which isn’t really possible for beginners, so I suggest looking up pictures taken with the cameras that you are considering on Flickr or Google. For instance, if you search Canon F-1 on Flickr Groups, you’ll find a group filled with pictures that different people have taken with that camera.
See also ‘Where should I buy a camera?’, ‘Where can I buy film?’ and ‘Where can I buy photography gear?’
If you need more questions on this subject answered, just put them in my ask box.