That's a tough question to answer, like asking which Ice Cream flavor you like the best, your going to get tons of answers and they all will be different, but I had the same question not so long ago.
I first started looking on Youtube and researching most of the applications that I thought I could master without any difficulty, I am not tech whiz, but just enough to get in trouble.
I tried some free 30 day downloads on some programs (Adobe, Sony Vegas, Pinnacle etc) some I felt where too much for me to master. I started to focus on one type on Youtube and finally settled for Magix's Movie Editing program. I bought the program off Ebay at a discounted rate, although on the website there is a trial period for 30 days to see if you like it, as there are for most video editing programs.
It only took me a few days of self teaching to be able to produce some acceptable results, but I keep improving, adding new stuff etc.
Have fun in your research and I am sure there are far better experts on this site that can assist you.
PDR