Hey, sorry to hear your about the freezing. The easiest way to update your system is to go to the apple in the upper left and select software update. Because you haven't done it for a while, you may have to do this several times until it tells you that your software is up to date. I think you'll be just fine. I'm running on the latest firmware and haven't had any trouble with it. Remember that when the computer manufacturer is also the OS manufacturer there is less potential for updates to ruin things because they are built to work together.

That being said, nobody can really anticipate what will happen. You aren't running any uncommon software though so you should be fine.

Using the method above, your mac will tell you what each of the updates are for. You might find that your mac runs smoother, and has fewer hiccups with the updates than before.