my car reves on its own and kind of jumps?

sounds like your airflow meter controlling your fuel injection,
when this is faulty your car will tickover erratically, so when stationary your revs will be up and down and it will run rough and jerky due to incorrect air/fuel mixture.
the airflow meter is the electronic sensor fixed to the intake between the air filter and the engine.
your local peugeot dealer will be able to plug your car into their diagnostic equipment and tell you the exact problem but chances are your airflow meter is at fault - easy diy repair and plenty of pug breakers out there - just make sure you have the right part number because there will be a couple of different ones

mike
January 2007