Battery
Next, clean the top of the battery of all grit, grime, dirt and liquids. Also clean your battery terminals and replace any terminals that are in poor repair.
Be sure to check the positive cable attachment at the starter. This has a tendency to become corroded over time. Corroded cable or connectors will result in starting problems.
If possible, check the battery charge. Places like AutoZone will usually load test your batteries for free, if you ask them.
Misc Check
Windshield wipers, spare tires and making sure you lube door hinges and your hood latch are all good ideas to prepare for the winter season. Consider using a dry graphite lube or silicon spray for all locks while you're at it. This is also a good time to make sure your emergency brake is functioning properly and that your disc brake sliders are lubricated and free.