Let me try to answer these. Obviously this is my opinion. hehe

1st question: From my experience two quadrants in a day would be too much for me. But that depends on you. How does your jaw feel after holding it open for 2 hours? Mine is usually on fire and that is with the dentist giving me breaks in between.

I'm not sure I could do that many, but it depends on how many cavities and amalgam replacements we are talking about. If you only have 4 teeth in both quadrants that need filled then it's doable. But if you are like me and had on average 5 teeth in each quadrant that needed filled you'll be sore. This doesn't even go into the potential for side effects from the work. My 2nd visit was by far the worse with mercury poisoning side effects. The others went totally fine.

2nd question: I have all 4 of my wisdom teeth and I've never had any dentist (including the crappy ones) tell me to get them out. I'm not even sure what the reason would be if they aren't coming in crooked or broken.

Yeah they can be really annoying to clean, but you just have to pay extra attention to them. Scrapping the back of them with a hooked pick is essential. A toothbrush can't get in here without banging off the side of your cheek.

3rd question: Yeah they say a high speed drill is bad because it will create more heat and mercury vapor. The dentist I went to did whatever he normally does. The only time I had ill effects was the 2nd appointment and I think because I had 5 cavities filled that day (1 amalgam removal). It was just a lot for my body to handle.

4th question: There were a lot of times where he would rinse and some water would splash up. I was thankful for the glasses, but if their oxygen is completely covering the nose then she is right. It won't work. I guess you could bring some swimming goggles? They are normally more flexible. =)

5th question: It took about 2 months to get all my fillings removed. My dentist will only schedule 2 hour appointments (at the most) and usually only 3 amalgams can get removed in that time frame. I can't imagine keeping my mouth open any longer than that and they are a very busy practice. It would be a few weeks in between appointments.
This is how my appointments went. 1 appointment for each quadrant. On the 3rd appointment I had an upper root canal tooth drilled out.

1st appointment-1 amalgam removed 3 cavities filled
2nd appointment-1 amalgam removed 4 cavities filled
3rd appointment-3 amalgams removed 1 cavities filled
4th appointment-3 amalgams removed

I had a lot of my new cavities filled before starting on the large amalgams too. I was really anxious to rip them all out, but going by quadrants made it easier. That way I didn't have to get more unnecessary novacaine shots and more visits. All in all I had 8 new cavities filled and 8 amalgams removed. Phew. My jaw has had enough.

Last question: All fillings have radioactive materials in them to show up on xrays. These are added so that when you go to a new dentist in 5, 10, 20 years they can see what dental work you have had done. I personally think this a good thing, but I can understand your concern. I doubt you'd find a composite that didn't show on an xray.

Just to add. My dentist did not follow the Huggin's protocol. However what is important is how well they pay attention to details. My dentist was amazing at this. He would make sure the bite was properly readjusted, wiped out any mercury residue with a cotton ball, used a rubber-dam and I had oxygen in my nose. I never had mercury pieces in my mouth after the appointments. Other dentists I would go to, a few hours afterward I'd be picking amalgam and tooth fragments out of my mouth. Yikes! Honestly he was the best dentist I had ever been to and I might write him a long thank you letter.

This might sound weird, but I'm actually going to miss him and his assistant. They were great people to talk to.