I went to a JC for my freshman year, then transferred to University. Unless you're going to one of those rare JCs that have dorms, you're missing out on a lot of University life.
Basically, a University will give you an orientation, etc, and then you're off living on your own in a dorm full of students your age. It's a lot of freedom and fun, and you'll meet a ****load of other freshmen. It's also a lot of work and some people blow it because they're more concerned with the partying than the school.
On the other hand, at a JC you basically commute to campus. Many young students are living with their parents still, so there's not nearly as much freedom. A lot of JC students your age aren't very serious about school and are just going because their parents would cut them off otherwise. You'll notice that your classes empty out about half-way through the semester. There are also a lot more adults working on their degrees at a JC than there are a U. You can get to know people at a commuter JC like this, but there are no built-in social institutions like you find at the U. Recent HS grads at a JC also tend to stick with their HS clique, whereas University freshmen tend to start over and form new ones their freshman year.
Essentially, University freshmen are going to have a lot more fun than you will at a JC. Don't let me discourage you too much--you'll be able to meet people at JC, just not nearly the amount you will at U, and your social group will not be tied to the JC.
Transferring from a JC to Uni isn't too hard a transition. You probably wont' be hit with the same sense of awe that freshmen come in with. And your classes at JC will prepare you for the slightly harder U classes. You won't have the benefit of being thrown in with a group of your peers who don't know anybody, like the freshmen do, but it's not too hard to invade cliques at University.
One of the nice things about the JC I went to (2nd largest in the country) is that it had quite a few hot girls. But most of these were just ****ing material and pretty stupid. The University I go to has a lot more hot chicks, and they're not annoyingly stupid.
My advice is to work your ass off your first two semesters, get a 4.0 at any cost (to your social life, etc.), and transfer to a University your sophomore year. If you're worried about money, don't. Universities have great financial aid if you're poor. Always keep in the back of your head that you're at JC to transfer the **** out ASAP, and you should have no problem doing what it takes to get to U.