Is Vanilla WoW fun even if you are not a hardcore raider?

I used to play Vanilla WoW back in 2005, but I was just a kid and never really got very far. I would just mess around and explore the world... never leveled a character past 20. So I never really got the full Vanilla experience but I still have very fond memories of that time. I tried playing retail WoW with a friend when Draenor came out and found it a bit overwhelming... everything just seemed very cluttered.
So I stumbled upon Nostalrius and am going to check it out! But will it be a fun time even if I am just questing and exploring at first? If I enjoy my time, I may get interested in becoming a more serious player but in the mean time, how is the leveling experience? Are there a decent number of people running around?
I understand that a PvE server is being tested on Sunday. I will probably roll a toon on there but I also plan on rolling one on the PvP server. Is there a lot of griefing in this game? I actually don't really mind it, I think it's kind of funny. I don't really get frustrated when I keep getting killed either, I'll just turn the game off for a while if it really becomes a problem.
So I stumbled upon Nostalrius and am going to check it out! But will it be a fun time even if I am just questing and exploring at first? If I enjoy my time, I may get interested in becoming a more serious player but in the mean time, how is the leveling experience? Are there a decent number of people running around?
I understand that a PvE server is being tested on Sunday. I will probably roll a toon on there but I also plan on rolling one on the PvP server. Is there a lot of griefing in this game? I actually don't really mind it, I think it's kind of funny. I don't really get frustrated when I keep getting killed either, I'll just turn the game off for a while if it really becomes a problem.