My car got broke into and now it won't let me start it, and I think it is because of the remote starter/alarm system? What do I need to do to get my car to start?

Disconnect the negative battery terminal.
Disconnect or completely remove the remote start system and restore the vehicle harness to it's original configuration.
Reconnect the battery.

my car got broke into and now it won't let me start it, and I think it is because of the remote starter/alarm system? What do I need to do to get my car to start?
What do you mean by harness?

What do you mean by harness?

Harness means the wiring that connects the various modules and components and allows the car to function.

If it was a professionally installed alarm have it professionally uninstalled. More people have had more problems installing and uninstalling alarm systems then I care to think about. If it is not done correctly you will be tearing your hair out trying to figure out why the car is disabled even after you uninstall it, if you don't know what your doing. It will cost you a little but in my opinion it is worth the cost.