If you're car isn't fast to begin with...don't drive it hard, IMO though. Since you have good mileage, stick with dino oil, don't go synthetic. Castrol GTX, Pennzoil, Mobil, Quaker State, etc...are all good name brand motor oils. As far as the weight, that's mainly up to where you live and what kind of climates you encounter. Down here it's mainly hot and humid so I use 10/30.