so she wants to trade in for an underpowered skittle and your glad? OK. Go for the screw-driver-backyard-shadetree-don't-have-the-skill-to-do-it-right-trick and that'll fix it....if it's a problem with the thermostat being stuck closed, however since the thermostats are made to open in the event of failure I doubt that will solve your issue. Replace the thermostat with a new one, and when you refill the coolant make sure you get out all the air that made it into the system, as air pockets can cause the coolant flow to stop or slow and therfore you'll overheat again. I would check for spark and if your getting it then I would say it may just be part of the overheating. I have had vehicles not start when they overheat, so after it cools down and gets fixed you should be ok. It is possible that the high engine temps affected seals in other components or overheated the sparkplugs which could fry the conductor inside the plug.