Man if it feels right and you dont mind the fact that she has a kid, go for it man. I personally dont mind it if a woman has a kid or not as i do have one myself. Just gotta remember that you are not his/her father and dont treat the kid like trash.
when I started dating my wife she already had 2 kids from a previous marriage. We've been married almost 12 years now. If you're mature enough to handle it then go for it but don't get mad because she can't make you her top priority.