Hey,
There are many great options available for free, non-commercial use, As recommended above, HitFilm 4 Express is a very good option. It allows for editing and visual effects in the same program, meaning it's easy to greenscreen or do whatever else you would like to do. Despite these features, I find it laggy and buggy to use, and you need an extremely fast system or it will glitch and close itself in the middle of your project, losing all your work if you do not save every few minutes.
My personal favorite option and current software is Blackmagic's DaVinci Resolve. Originally a color correction software, it has added a very competent editor that will fit all your needs. It also features an industry-used color grading package. Resolve 12.5 is free for non-commercial use from
https://www.blackmagicdesign.com/ca/...davinciresolve
I used DaVinci Resolve to color correct and edit this video, as well as many others:
https://www.youtube.com/watch?v=hAT6A2eCYro
Hopes this helps,
Matthew