I guess I'm over carbed

New to kegging.

Have a fridge set up with 3 taps. When I bought the kegerator it had 5 foot lines. Had the fridge set around 35 degrees. Put the regulator on 12 and left it for 2 weeks on my first 2 batches of beer. Lots of foam.

I have since turned the fridge up to 40 degrees, changed to 12 foot lines. I am still getting over about 60% foam out of the two beer kegs I put on the gas at the same time. Even with the regulator all the way down to nothing still get fast foamy pours.

The cider keg that went on later after the temps were up and lines were longer seems fine right now after 2 weeks on the gas.

I've released pressure a few times. I've put the little spiral inserts in one of the two kegs. Nothing has helped.

So what's next? Do I open the kegs, stir to get as much co2 out as possible and start over? Am I doomed to finishing a foamy keg and hoping the 2nd batches are better?

It does sound like you are overcarbed. Warming the fridge up after they are carbed won't change anything. You'll need to pull the gas off, and burp the kegs everything you walk by for a couple days until you get the right amount. If that doesn't work, you might want to check your regulator. Though I doubt that would be the culprit with you saying your cider turned out fine. Just vent the overcarbed kegs as often as you think about it with no gas connected for at least a few days... that should help.

Check the temperature gradient in your kegerator. I turned a chest freezer into a kegerator and I was having a problem where the temp of the lines was warmer than the temp of the beer. As such, the CO2 would come out of solution in the lines and cause the beer to foam. I put a small computer fan inside to get the air moving so the temp would be a bit more constant. I no longer have that problem, but unfortunately my kegerator turns on and off more often.