What will happen if I reset my cellular useage?

I have an iPhone 5 and I don't have a lot of storage left, so I went into settings and deleted some apps, but that barely did anything. There was something that said cellular usage and I clicked on it and it told me I have like 2 GB of received messages. First of all, does this have anything to do with my problem, and second, if I hit the button that says "reset statistics" what will happen?

No it has nothing to do with the phone storage. That's how much cellular data you have used. You can reset it and nothing will change