I am altering a system i found in a library to suit a game i made (may as well be honest, eh? :P) for a text box appearing on screen when the user talks to an NPC. I already have altered it to work with my text and textbox sizes etc, and have made the text "!type" onto screen. It works, but i have a question:

Which would you prefer to see in a game?
a) Waiting till text finished typing before it was closable?
b) Being able to end the typing text prematurely (skipping)?

I know the probable answer to this for most of you (b), but i want to take into account that a lot of these text boxes are for the storyline, and i dont want people to be complete n00bs and just continously skip through text chats all the time...

But anyway, what do you think?
If they are core story bits, make them unskippable. But given the potential for annoyance, care should be taken when deciding which ones are unskippable, as it should be as few as reasonably possible. Having the option to skip for all other NPC dialogue makes sense.

A somewhat related issue is dialogue short-cutting, commonly seen in Guild Wars. You first discussion with an NPC may be long, to provide the story dialogue. If the player has cause to talk to the NPC again, the dialogue presented was much shorter, such as "How are you progressing?" "What can I do for you?" "Oh, you again." etc. Combined with an option to replay that story dialogue again, this reduces the design need for skipping dialogue, and lets the player get straight to what they want.
In response to Stephen001
What about making it so that if the text is still typing and they try to close the box, instead it instantly added the rest of the text? Would that be a good feature too?
In response to SadKat Gaming
That should probably just be close, as it's quite a natural user action associated with that button.
In response to Stephen001
I was just thinking of using that as a way to interpret the skip function. An added bonus to this method is that if a player is a particularly fast reader, and the letters are typing too slowly for them, then they can just make it all instantly appear for the sake of quicker reading.
In response to SadKat Gaming
Clicking in the general area of the box itself is a common way of doing that, I've found.