Which one is better for a 2000 Honda with 100k miles?
How often change the oil - mostly city drive?
Unless your Honda requires synthetic oil (which I doubt it does), then I would only use it if I needed the added benefit of very cold weather starts (like often below 0F).
If you do mostly city driving, then change it per the severe maintenance schedule.
I believe the Honda manual calls for changing the oil every 7500 miles for normal driving and ever 3750 miles for severe driving.
If you mix your city driving with long drives, every 3750 may be more often than you need.
I would use the least expensive mineral oil of the correct viscosity and change it per the severe operating conditions schedule that Honda provides four your car.
Either motor oil is fine for your vehicle. Mobil-1 is very good oil–there’s a reason racers use it and that it’s factory fill in high performance cars. If you live where it gets very cold, synthetic oil is likely going to protect better at start up, as it will flow quicker. Synthetic also handles heat better without breaking down. Synthetic is better oil, but may be overkill for a grocery getter. You decide whether it’s worth the expense to you. There are also many synthetics besides Mobil-1. I personally have been using Amsoil in my vehicles with good results.
I would probably change the oil every 4-6K miles. More towards the 4K with “dino” oil, more towards the 6K with synthetic.
The most important thing regardless of what oil you use is to make sure you never run it low and change it regularly.