Lol, that's like asking hundreds of people which is better, chocolate or vanilla. You'll get a multitude of answers, maybe even some mixed! If you're interested in multiple riding disciplines, then ride multiple disciplines. Personally, I am partial to dressage, but I also love jumping, western, pleasure and trail, so I made sure that my horse was comfortable doing all around stuff from the get go.
Feel it out, take some dressage lessons, maybe a reining and a saddle seat one here and there, try some gaming, try it all. You'll eventually learn what you're most interested in and focus your practice in a bit more.
For now just enjoy the ride :)
We are not human beings having a spiritual experience. We are spiritual beings having a human experience. -Pierre Teilhard de Chardin