Kettle bells are awesome tools to have in the box. The nature of some of the more popular movements really fire up EPOC. They also require a tremendous amount of motor unit recruitment which utilizes fast twitch muscle fiber. Those are the muscles that make you big and strong. The more muscle you carry the more efficient your body is at burning fat.

I would suggest that if you want to train with kettlebells you find someone to instruct you in proper form.

I'd agree with phrakture; start easy with body-weight exercises and, IMHO more importantly, full-body/muscle-group/compound exercises. This will develop overall strength.

You can use dumbbells once you're ready to take the next step after body-weight and you can do most of the same exercises with dumbbells as with kettlebells.

Personally, though, I prefer kettlebells. I tried a set of dumbbells and a barbell after quitting the gym and noticed I spent more time adding/removing weights than actually lifting them, and the clutter they made in my bedroom was awful. I don't have much room to exercise in, so I switched to kettlebells and do lots of compound exercises (mostly squats) in a 2x1m area.

If you've already have some weights to work with I wouldn't switch unless you're sure it'll help. Maybe try an introductory session at a gym where they have them?

There are some exercises that I found difficult to do with dumbbells which made up my mind to switch, such as weighted squats, clean+press, etc. KBs rest more snugly on the arm than DBs do, plus you can do swings which fire-up the posterior-chain (tightens the buns and lower back muscles).

Would video instruction be sufficient or do you think I would need an actual trainer?