If you like DnD you'll absolutely love this server. These lovable losers play it all the time. There's not much active roleplay on the Minecraft server itself, mostly in the forums and when the guys play DnD, but we occasionally arrange lore events for certain places that people have built, and you can arrange events with others.
Also since you mentioned you love exploring, there is *so* much on this server. I've been on since October and I don't think I've seen half. (Granted, I don't do much exploring myself). But there are so many settlements that people have finished and moved on from, old cities being expanded or improved.
You seem like you'd be a great fit, so just reply when you can and maybe provide some images.