Normally my car doesn't miss a beat in starting. Today it refused to, it was a loud click and the lights turned off. If I did it more than once the lights on the dash didn't turn on at all. We tried different batteries to the same result. I think it might be the battery terminals. But is there anything else I should check?
Got a multimeter? Strange it did it with different batteries. The starter motor could be defective. Check the battery voltage, if it is about 12.7 volts it is fully charged. 12.2 volts it's about 50% charged & discharged or dead flat at 11.9 volts. If you suspect the battery terminals, check resistance between the terminals & battery posts using ohm's. A good connection will indicate a similar reading as obtained when touching the test lead probes together.
If your car is auto it might be the starter solenoid, but if there are audible clicks it might be your starter.
Looks like it definitely was. I'll pick up some new ones. I suspect it might the leads too. What resistance am I looking for?
also check the inside of the battery clamps as well there can be corrosion there causing bad connections.
Most likely stuffed starter. Have someone bash it a bit with something while you try to turn it over.