Once again, sorry about your car man.
RedSunCelica said it right: you want to run stock first, and once you've expanded your abilities to the limit of your car then you can start modding. The only thing I'd say is to consider some decent tires (not the best you can buy, just something that'll let you have fun), they can mean a world of difference (especially if the car comes with some rather poor tires).
A manual is slightly better because of the shorter gears, but a good auto driver can beat a lesser stick driver.