Hello George and welcome to the best site on the internet. Everyone has their own opinion about what should be cooked at what temp, over time and some smokes under your belt you will have your ideas. Certain cooks like babybacks and sometimes Boston butt I like to do at a higher temp, heck from what I have read some only do brisket at high heat. I don't know, haven't tried it yet.
There is tons of great advice on here, so you are in the right place. One of the best things I learned early on from Kevin Kruger is when you try different things as far as technique, only change one thing.
Some do a cook then change the temp, smoke wood, and dry rub. If you only try one different part it is easier to figure out what works for you and what doesn't. Have a good one.
Eric