Your engine is backfiring when you start it. I have a 4 stroke that this happens on when I start with a chicken stick. With an electric starter I don't have this problem. There are tricks to getting it to go the right way without restarting it...but I wouldn't recommend it for a 'beginning' forum topic.

As for TX batteries - if they are NiCad's - yes they can. The best thing to do - cycle the battery every month, and you should be fine. If you don't have a battery cycler- just turn the TX on and let it run for about 1-2 hours....unless you TX have an auto-shut-off.