I reckon you’ll be fine with a regular reserve and ride. It depends if you make the most of your time there. If you can get there for 9.30 (at least) and stay until the park closes, you’ll be able to do quite a lot without R&R.
There are several queue- free attractions such as Lego Reef, Miniland, Brickville, Star Wars miniland experience, rock climbing, Kai’s Spinners, Jay’s Lightning Drill, temple build, castaway camp, enchanted forest, splash safari and the model making studio. There are also shows. Do all these during the busiest times which are late morning and mid afternoon. Do the popular rides first thing, last thing and during lunchtime. You can tell which ones have the longest queues as they’re the ones you can get a R&R for.
Miniland opens 30 minutes before the main park so you can walk around early and you won’t miss any valuable time in the park itself.
Food is very expensive there and everywhere to eat has long queues so its best to take a picnic. we headed to one of the local supermarkets (Tesco in Bracknell, which was on the way to the park) and spent £12 on lunch, drinks and snacks for the five of us. Friends from home who we’d bumped into at the park had spent around £80 on food and drink over the course of the day. It hadn’t occurred to them to do this.
There are plenty of spots for picnicking, or you could eat it in front of a show or in a queue to maximise time. If you choose not to bring a picnic, aim to avoid the usual lunch hour rush. Restaurants are usually jam-packed between 12-2pm. Try to eat outside of these hours to avoid long queues for food and seats.
Some of the rides have Lego to play with along the way; Sky Riders even has an area where kids can sit and watch various Lego films while you stay in the queue (although this may well not be happening now).
The usual advice is to leave the wet rides until the end of the day so that you don’t have to walk around wet and cold. However, because everyone does this, that’s when the rides are usually busier. Consider taking spare clothing so you can go on them earlier and then get changed, use one of the family drier cubicles (costs £2), or bring waterproofs. You may be at risk of being unexpectedly squirted or sprayed on the Heartlake City Express train and at the live harbour shows – depending where you sit.
The toilets are quite well maintained, but towards the end of the day there can be a distinct lack of toilet roll. I recommend coming prepared with tissues.
Just a little thing, but unlike most lockers at swimming pools etc. the lockers in Legoland do not refund your coins as you might expect, so beware. There are notices which state this but not everyone reads notices.
When we arrived, even though it wasn’t yet 10am, the park was already really busy. There was even a queue to get down the path into the main park. Ignore his path, to the right of the entrance, and instead veer left to avoid the crowds. The kids will love this route because they can whoosh down the slides rather than the steps.
We found the Legoland app invaluable while we were in the park. It helped us to know which rides to avoid and which to make a beeline for when they were quiet. There are signs around the park with wait times, but this was far easier to use, with Legoland’s free Wifi.
In the evening, Windsor has some lovely restaurants. We ate at the Bell and Dragon in Windsor which was very family friendly and even had chalk tables that the kids could draw on.