Ernest:

First and most obvious questions: are the alternator/water pump pulley belts tight? When was the cooling system last flushed? If PO can't remember, then it's way past time! The temperature gauge rising to the red while you're stopped at idle, then going right back to normal as you drive sounds to me like not enough air flow through your radiator, which means your fan clutch isn't working properly. Try this simple test: idle the engine until the temp gauge is up near where it was when you noticed it at Taco Bell. With the hood up, shut the engine off and watch the fan. If it stops immediately with the engine, the clutch is OK and you/we need to look elsewhere for the problem. If the fan "freewheels" to a gradual stop, the clutch is bad. They're not too expensive, maybe $50 or so at the chain stores, and easy to replace. Four 10mm nuts hold the fan assembly to the water pump pulley studs. Remove the assembly, then four more 10mm nuts hold the fan to the clutch. Fifteen minutes to R&R, tops. But while you're at it, take the fan shroud off (two Phillips screws) and use a garden hose with a spray nozzle aimed at the back side of your radiator, and blow out all the bugs, dirt, etc. that's likely stuck in the radiator fins. That'll help with airflow through the radiator, too.