i've got the 2.35s on my 26in bike, they look more like 2s. wouldnt go any smaller especially at those parks. you'd never notice the weight difference riding at those places imo.
btw, i know you didnt ask but i dont really like them. even at really low pressure still feels like i am riding on plastic big wheel tires. they were crazy cheap a while back so i gave them a try. i dont ride that bike much so dont have the energy to take them off. maybe if i wore them in more they would feel better? never flatted tho...