I SWEAR by the Lowepro Slingshot. I have a ton of camera bags for different kits, and the only one I use when I'm doing work on my feet with more than just a camera and a lens is the slingshot. I *think* the 100 (the smallest size) would be a little tight for your needs. I use the 200 for my main work kit.
In the top, I carry cords and such, but you could easily fit all the film you mentioned in there. In the main compartment, which is configurable to your needs, I carry a D700 with a 50mm attached, a 80-200 f/2.8 (which carries horizontally when the bag is upright, the bag is wider than you might think), a 24mm lens, a full size flash and I have plenty of room to spare. I often toss my Minolta Flashmeter in there, or my Nikon L35AF, and it's still not cramped. The front pocket is where I keep my Moleskin notebook and business cards, but some film would fit in there, too.
AND (can you tell I love this bag yet) the sling action really works well. When I'm toting my bag I where it like a backpack, but when I'm work and getting in and out of my bag, I sling it down and it works just like a shoulder bag.
You also get a couple of bonuses. First, there's the rain cover, which again, actually works, but stays out of the way when you don't need it. You also get a secondary strap to use when you're on the move. I only use it when I'm hiking and biking. When biking or bending over a lot, it stops the bag from rolling around to the side.
I think it would be perfect for your needs.