which framework to choose?

There is no one best framework, silver bullet, and no one feats them all. Fusebox is easier to grasp and makes the transition from spagetti code easier. Next is Model-Glue, which makes Object Orientes developing a little easier, and Mach-II is the stricter of all. ColdSpring is the newest one out there, not nearly as popular as the rest. Model-Glue: Unity integrates with Reactor and ColdSpring, however, Mach-II has plugins for both frameworks available. There are examples and ajaxCFC uses for Model-Glue and Mach-II, and Spry examples for Model-Glue. Mach-II just added application.cfc support, which Model-Glue does not have yet. Model-Glue supports 'actionpacks', which are powerful subapplications, are really handly addition.

If you're not familiar with objects, go with fusebox, perhaps it doesn't even require you to use them. I personally like Model-Glue the best, but again, that is a bias personal opinion. I would suggest you try them as which one feels better.

Regardless of your decision, if you are to get into heavy OOP, I would advice to adopt ColdSpring for your wiring needs.