WARNING: Complete Newb

This downloads all the current updates for all areas of the game at once so you don't have to wait for them every time you enter a new area. This is a one time thing, so if they do updates after you have run that command, you will have to do it again to get the newest updates(or just do it once and put up with the smaller updates as you enter different areas). It certainly does save on the bandwith while you are playing though.

OK. How common are updates, BTW, and if I don't look on the website will Guild Wars still tell me about an update if I load it?

Also, does that mean that if there are no updates, every time I load Guild Wars after doing this, I won't need to load a new area ever again?

If you do the "-image" then you won't be downloading anything until the next update from Anet, which comes whenever they have something to update, no set schedule. It is pretty common for a large update to be followed with smaller ones as they tweak something or fix something they broke.

The updates come whether or not you do the image, using the image option just takes care of it all at once so you don't have to deal with downloads while you are playing.

Updates seem to usually happen towards the end of the week(thurs-fri) unless there is an emergency update. They don't seem to happen every week. Guild wars will only tell you in game when there is a critial update, and it needs to be restarted, otherwise it downloads them in the background while you play.

If you want to make sure you are up to date, I suggest running that command once a week on average. You can copy the guildwars shortcut on your desktop, go into the properties and add the -image to the target path(outside the quotes) so you can run it whenever.


edit: forgot to answer your second question, as long as there hasn't been a new update, you can access any area without waiting for it to download files.