The best deterrent to becoming a parent is becoming a teacher. @
RD McFly is spot on - being a parent is easy, all you gotta do is dump deep in a bitch. Being a good parent is enormously difficult. I'd say, at a conservative estimate, 80-90% of the parents I have to work with (my students' parents) are on the shitty end of the parenting spectrum, and I'm sure they're all convinced that they are the best parents ever. Supporting kids is more than hanging out and having fun, it also means building character and moral integrity which necessitates conflict with them (telling them no, discipline, patiently illustrating when and how they are wrong, etc).
Personally, I don't plan to have kids for at least another 8-10 years because I want to travel and accomplish more in my personal and professional life. But I believe Lars is a good dude and capable of raising kids due to his topical prowess. Just make sure you have the finances to have kids; love is the easy part, paying for them is difficult. Best of luck.