Hi Nadim,

A lot of the answer will depend on which theme park you are in and where in the theme park you are. Assuming a Disney theme park, if you are at the far side of the theme park you might have a 20 - 30 minute walk back to the entrance. Longer if you stop off anywhere on the way. From there you've got potentially a 5 minute wait for a tram, 5 - 10 minutes on the tram and then a couple of minutes walk to the car. Then you reverse it all back to the theme park.

Magic Kingdom is a longer trip as you have the monorail as well, so you'd go theme park -> exit -> monorail -> ticket and transportation centre -> tram -> car park -> car.

That said we have lots of guests who head back to the villa for lunch. They like the idea of avoiding the middle of the day in the theme park where everything tends to be busy and the queues tend to be at their longest. There's an added benefit too that on the return trip it's often possible to park quite close to the theme park entrance and so skip the tram ride. This is extrememly handy at the end of the day as you skip any queue there might be for the tram and just walk back to the car.

For the Universal theme parks (Universal and Islands of Adventure) I'd say to figure a half hour from the park entrance to the car park, and then the same back. Another option though for lunch at the Universal theme parks is to head out of the park and just walk across to one of the restaurants on Citywalk. The food is better than you'll get in the theme parks themselves and it's a great way to just chill out for an hour or two and recharge your batteries ready for the next half of the day.