We always travel as a family (not part of a convention), and we have been at CSR when there were conventions going on. As a PP said, conventions are usually a non-issue for leisure guests. You might see people walking around in polos and wearing nametags, and the lines for breakfast might be longer than usual, but conventions usually mean the buses and pools are empty during the day.
The one convention I caution people against if they are not participants is the Grainger show. It is generally held the last week of February into the first week of March, and they pretty much take over the whole resort. If you are not planning to go at that time, you probably won't notice much at all.