Always Shoot in RAW (or highest resolution & finest JPG)
I know that many readers feel that they don't have time for shooting in RAW mode (due to extra processing). But during some condition which you can't miss that moment (Wedding, Traveling...), RAW can be particularly useful as it gives so much more flexibility to manipulate shots after taking them. Some time tricky lighting which result in the need to manipulate exposure and white balance after the fact - RAW will help with this considerably.
Your camera doesn't support RAW mode? Shoot at the highest resolution and the highest quality mode. By doing so, you ensure your photo has the highest potential for the future use.