Well, from what you have mentioned before, it sounds like you are pretty familiar with some of the guidelines of the church. Such as not dating until they are 16 years old and such. But the answer to if you have a chance with him, is that it really depends on him.  
 
True, we are encouraged to date within our own religion, because of the standards which we have, like abstinance before marriage. But also it is because of the blessings that we are able to take part in if we are worthy and faithful to those standards. Those blessings are given inside our temples, and the one most talked about is that we have the chance to be married "for time and all eternity" rather than "till death do you part".  
 
There are people within the church that do date people who aren't part of the Church, but that really depends on each person's individual choice. (as does everything :P ) So I guess the only way to find out is to go and ask him what he feels about it.

there's this guy who's mormon in my school, and he's 13 and so am i, is there anyway we could go out? or can he not date til he's 16?

To the person who is 13, again the best thing I think you could do, would be to just ask the guy. Explain to him that you have heard that he's encouraged not to date till he's 16, but you would like to date him. I'm sure he would be flattered, and you'll get the answer straight from him.