US can't connect to the euro servers afaik. Mal'Ganis is a US server. It's located in Central time zone somewhere. It's also got a ton of Horde players compared to Alliance.
PvP servers work this way: Up until level 20 you are safe unless you type "/pvp" or you attack an enemy player, or you assist someone in battle by healing or buffing them. Once you hit level 20, and you enter a contested zone you are flagged for PvP (and once you leave that zone, you are flagged for 5 minutes thereafter).
On a Normal server, you do not get flagged unless you type "/pvp" or you attack an enemy player, or assist someone in battle by healing or buffing them. There are no contested zones.
Right now, PvP is pretty lame because you get high level players that hang around low level areas killing the quest giving NPC's and the vendors, etc. There is no penalty for this, and they can do it however long they want, and that level 50 rogue will camp your level whatever corpse if you attack him.
Also, large scale PvP can sometimes be fun but a lot of people don't get it. The healers don't heal, the casters don't use area of effect spells, etc etc etc. Some groups get the idea, but for the most part players will start attacking someone until one of the two dies.
Hopefully, Battlegrounds and the PvP Honor System will bring some fresh air to what is not a fully implemented system at this time. But, apparently there will still be no penalty for ganking low level players. You just won't get any rewards.
Personally, I am still finding PvP to be much more exciting because it's pretty tense when you know that you are in danger out there. It's also fun to be running around with your full party of players and then run into a group of enemy players and engage in battle.
Anyway, that's enough out of me. Hope that helps.