Purchasing Guild Wars in S.Korea?

If I purchase Guild Wars in South Korea, will I be able to play in the american and European servers? Or will I be purchasing a different version of Guild Wars altogether

You will be able to play wherever you want! You won't be limited to any one server at all.

So there is no separate CD keys for Koreans and Americans? Is it like Battle.net where you can purchase it anywhere but you can connect to different regions?

I think the CD Key does contain a sort of region data to it, but that only allows you to add Asian language characters to your name and such. And the way you connect to other regions is simple. You kinda don't. When you're in a town, click the drop-down menu from the top left and select the more/advanced options one and you can select the districts you want to go into. For example, you'll see European, with several options, American wit only the english option. I'd say American English and European English are your best bets to find lots of people. You can form parties with people in any part of the game from any part of the world with no hassle. When you go out into the adventure world your party gets a private copy of it. That counts for you being alone or with people as well.

*EDIT* Slight edit...

Your account will be on asian servers so when you log on and stuff you'll have to switch to american everytime. You'll also have a higher ping since you'll be connecting to asian servers.

Like if a euro goes to an american district and has higher ping.

asian is merged with usa one

no all servers r in us

Not true, it remembers what server you left off last time you were on...

And by server I mean district.