The first time my DH and I went (year before we were married, and his first vacation ever), we were 25. We went from morning until midnight (okay, we were young!), taking a break midday back at the hotel (well, kind of motel with a kitchen, a Residence Inn in Kissimmee that has long since closed) to eat lunch nearby and rest during the afternoon downpour. We didn't eat any meals at the parks (couldn't afford to) but closed down Epcot only to monorail over to MK for another two hours regularly.
That was then. Never did that again in all my trips (and not all are listed on my sig).
First time we took both kids (they were 2 and 4) we went for 10 nights (2001). We took it easy and just did what we felt like. We weren't sure we liked DAK - well, spent so much time wandering around that we just had the best day ever! Kids fell asleep in the stroller in the afternoon - we pulled up to the Bawa Bar, had a few Red Stripe beers, chatted with the awesome bartender, just chilled and really relaxed and hung out. Best Time Ever! Anyone with a 2 and 4 year old knows - kids are happy (and asleep for a couple hours, really!) makes us happy!
Son has severe asthma (and many other health issues) so we learned to do just a few hours at most during a day at a theme park. We enjoy wandering the Boardwalk watching the entertainment as well. There is so much to see and do if we take the parks slowly too - my kids have their favorite things, so I just kind of go with the flow.
Last August, I took the kids myself for 15 nights. We had condos (switched after 4 nights) so I cooked most meals, we hung out at the resort, swam, did 10 day park hoppers with WF&M so did mini golf, spent maybe 3 hours at each water park (storms, LOL), and one day we literally just hung out at the condo all day in our pj's. Did a lot of Disneyquest too - they love that. Me, it's fun, not the best but fun. One thing I am so over is table service meals at Disney - rather do counter service snack food. It's quite pricey and we aren't huge eaters (except for my skinny 16 year old, but he's got attention issues so even he would rather eat a snack at the parks and have a meal later in the condo).
So, I guess I'd say when I was super young, on one trip, we did commando. We had a blast. We never did it again! Now, I wake early and have coffee, maybe do laundry, then rally the troops. It's a good day if we're out the door by 9am (summer heat). Doesn't always happen!
Also, when my kids were little, we kept to their nighttime schedule for the most part. They were asleep by 8 or so. Then we could relax and recover from all the walking (and we're quite fit; DH is a marathon runner and I run and work out too, but Disney is easy 10 miles walking in a day).