Look anywhere on the web and you will see people trying to find the "best form of exercise" for their goal. And, of course, they get a lot of different answers. Really, the answer is easy.
The best form of exercise for you is the one that you will do consistently to meet your goals, whatever they are.
Looking to grow stronger? Build muscle? Look for a weight training program that includes exercises that you enjoy.
Looking to improve your cardiovascular fitness? Look for an activity that you will look forward to doing.
Of course, this is a little bit over-simplified and may not help those at advanced fitness levels. Obviously, if you are training for a bodybuilding competition or a marathon, you need to do specific programs designed for that. But if you fall into the majority - people just looking to get in shape - this rule applies.
I personally follow this rule. When I was prepping for competition, I had picked up running. It burned a lot of calories and I could do it anywhere. Problem was, I hate running, and always have. Now, put a basketball in my hands and I could run all day. But to run for the sake of running? Ugh. The result was, once I got past the competition, cardio became an activity of the past.
Once I realized that I was creeping back up to weight I didn't like and wanted to introduce cardio again, I went straight back to running. And, not surprisingly, I still hated it!
One day, I was sitting in the crowd watching my younger son in taekwondo class and realized that was a pretty good cardio workout. When my older son discovered that they had a family class that we all could take together, I signed up. It's over a year later and I still love it. I go at least twice a week and look forward to most classes (I won't lie - jump rope week sucks). In addition to enjoying it just for myself, I get to do it side by side with my sons.
So, whether you like to run, do martial arts, play soccer, do Crossfit, powerlift, or whatever, it doesn't matter. For overall health, just getting off the couch and moving around is a step in the right direction.