You may be embarrassed to find, when you become a vegetarian, that you're gassier than before. Your body will eventually adjust to the change, but in the meantime you can try eating very slowly and trying to avoid swallowing air. Alternately, chew some activated charcoal tablets before you eat.
When you switch to the vegetarian lifestyle, one of the things you should remember is that you don't need to give up meat always and forever. It's OK if you want to eat some turkey at Thanksgiving, or eat a few spoonfuls of Jell-O for dessert occasionally.