with both daughters, I started around 2 1/2, but every kid is different.

There is some great advice here.
My three kids were all potty trained right around 3 years old. I'm sure I could have done it sooner if I pressed the issue, but I wanted it to happen on it's own and not have tons of stress about it. I did the things leading up to it, books, talking about it etc. All my kids basically said thy didn't want to wear diapers anymore and that was it they would start using the potty on their own, of course I asked them every so often if they needed to go, because they can put off going potty if they are really involved with something and having fun.
(once my son had Woody undies on from Toy Story... he accidently wet his pants and was so upset with himself crying that he peed on Woody!, it was so cute)

Best wishes!

2 is awfully early for a boy. My older boy is 31 months and he will go when I prompt him, but he does not seem aware of when he has to go. I think that's a ways off. I'm hoping he'll be more consistent by the time he's 3.