Great explanation of how to do the ties at the bridge end. That's the part that had me baffled. I hope my next stringing will be a little prettier after your tutorial.
If anybody is still insecure about the knot even after watching the above video, try this video. It shows a closeup of the bridge knot, including a large model of the knot using a 2x4 and some rope.
Yes, zillions. And there are quite a few threads about "the right" strings here already. Apart from the different tunings (re-entrant vs linear) there are also different materials (basically nylon vs fluorocarbon) in use. Have a look at e.g. The Southcoast Guide to Tuning and Strings for a first detailed overview.
If you play regularly, your strings will reach a point where they need to be changed. In my case, when I notice my strings are sounding a bit dead, it means they need changing. I usually wait too long before I notice, and the new set of strings makes a huge difference.