For years now I’ve been sailing dinghies, but recently have started sailing a Dart 18 catamaran. I can highly recommend these as they are much faster than monohulls, meaning you can go further on the same tide or just have more fun flying around a set course significantly faster than the dinghies 
I try my best to have a few sailing trips away each year, and my favorite inland locations are Lake Windermere and Rutland Water. Windermere is more oriented towards larger (expensive) keel boats, whereas at Rutland Sailing School you can hire all sorts of different boats and all the equipment you need (gloves, wetsuits, buoyancy aids, etc) at a very respectable rate. To hire a boat on your own you’ll need to be at least RYA level 2 certified, but if you’re not and you’d like to give sailing a try, for a little bit extra you can have an instructor accompany you.