If the car turns over, but won't start, look for a loose coil wire. Sometimes a car will shut down for unknown reasons and restart an hour later. If after an hour you're still stuck, try to write a note to leave on the antenna or windshield. Include the shop you want the car to be towed to if there is any preference and the direction you went for help. Always lock your car and walk as far off the road and onto the shoulder as possible.
Synthetic oils are far superior to conventional oil.
They lack the organic compounds that petroleum contains and thus don't deteriorate as easily. You can drive from 7,000 to 10,000 miles between oil changes as opposed to 3,000 to 4,000 miles using standard oil. If you buy a new car and plan to keep it for at least ten years, you should use synthetic oil. Use it for it's entire life, as the engine will probably last considerably longer. The scale ranges from 10w to 90w for most applications.