1. sounds like you need to spend more time with skiers outside the park!
As for the boots, don't worry about what fits with what, just go to a bootfitter and talk to them.
Talk about where you ski (resorts), what types of runs you are on the most, how many days a year you ski, how many years you've been skiing, the equipment you've used before that you liked...talk to the bootfitter about your needs, desires.
Boots, like skis, are different for each foot/person. while there are boots that are more tailored for specific things (racing, freestyle) you should go get fitted first.
Might I also suggest looking at some of the gear guides to get a rough idea of something that might be up your alley, then you can at least have a few models that you would like to try to see if they fit or not.
But what everybody has said above is key:
best to go talk to a bootfitter first and get set-up with boots.
You'll need to allow yourself at least a full day to try on boots (more if you feel the need to hit up a couple different shops should the first one you go to not have what fits...I had to hit up 5 shops before finding a boot that worked).
And then yeah, once you've got the boots, then demo for a bit. Try different lengths of the same ski as twin tips, especially, ski short.
It's a process, my man. Heck, I bought a fleet (5 pairs) of skis 2 seasons ago and it took me a season to figure out each ski and in some cases decide that I didn't like some of the models that much afterall. Then I demoed some more, tweaked my quiver and whatnot. But the boots were the key thing. Once I got a solid pair of boots, then it was all gravy.