1. Paper towel works fine but a lot of people have good luck with linoleum, indoor outdoor carpet or even towels James Hatfield reccomends a substrate made from a combination newspaper and paper towels
2. We have a radio going quietly where the iguanas are at 24/7 and they do well but if you're talking about loud noises then probably not so good as they wouldn't have a very "restful" period.
3. We usually use heat lamp and UVB with a space heater that comes on if it gets too cold for the overall temp. I'm sure there are lots of other ways but this works for us.
4. They usually don't do as well on smoother/slicker climbing things. Anything would have to be angled or textured enough to get a good hang on it. We use dead tree limbs etc that have been bleached/baked to make sure no lasting parasites or anything.
5. Collard, mustard, green beans and squash are a good start but can also be helped with frozen/canned foods as long as you add back in any vitamins lost in the process and don't buy ones with additives. They need a good variety. Berries are a pretty good fruit. Melons are okay buy I don't think they have a lot of nutrients. Fruit should really only make up around 10-15% of their diet. Just remember variety is a key and if you're not sure about a veggie don't make it a main staple but can probably be used once in a while or as a treat
6. Some people say 2-3 days some say 2-3 weeks. We usually leave them alone for a week with only feeding and cleaning and then slowly start introducing them to your hand being around then being touched, etc. Don't grab from above if it can be helped or they think you are a predator. They will probably think you are a predator anyway since you are bigger then them just give them time and remember they are wild animals and even "nice" ones are never completely domesticated.
Hope this helps some
Stephanie