I want to have kids someday but my boyfriend doesn’t. Otherwise I love almost everything about him. What should I do?

I know that if I do move on, he will be heartbroken and so will I. I don't think I'll ever find another guy quite like him. He has shown me, in more ways than I can mention here, how much he cares about me. He seems determined to give me everything that I want, except a baby. After all that he has done for me, I will feel like such a jerk for breaking up with him. And my family LOVES him. If I break up with him, they will probably demand an explanation, and I don't know what I will say to them. If I tell them about wanting kids, most, if not all, of them will probaby tell me that that just wasn't meant to happen for me. But maybe that is what I have to do. Also, there is another guy who has shown interest in me, but I don't know him very well. I don't know if he wants to get married and have kids, but he did ask me if I would like to go out to dinner with him sometime. But then, this was several months ago, and I haven't seen him in about six months. (At the time, my relationship with my current boyfriend was just beginning, and I wasn't sure where it was headed). I managed to find his phone number and email address through PeopleFinders, but I don't know what he would think if I called him or emailed him now. Would it be inappropriate to contact him at this point? Also, I should probably end things with my boyfriend before I do this, if I do. What do you think? Should I break up with my boyfriend and call or email this other guy? What if this other guy wonders why I am calling or emailing him now, and not several months ago? The plot thickens . . .