Little yellow lightning bolt on the log in screen

Right befre you log in, at the top by the minimize, it has the little symbol, and then, XX.Xmb. What is that for?

that is the amount of content you are downloading.

tells you how much you downloaded while logging in (factions content mainly)

Oh well, right now. Its at like 17mb. Its just sitting there, so I get time on Xfire, because i played it while xfire was off a fwe times.

Whenever there is new content available, GW will try to stream it onto your computer whenever it can to help shorten the length of the downloading/loading screen when you zone into a new area. While you're in game it looks for opportunities to use latent bandwidth to download the files in the background, but when you idle at the login screen, it uses as much bandwidth as it can to download any new files you don't have on your computer yet. So, if you see that lightning bolt with the X.XXMB next to it, it might be a good idea to let it sit there for a minute or two to let it download stuff for you.

Is it bad if it goes up to 38.MB like mine?

If the GW client is downloading it, its never a bad thing. That just means faster loading time in the future.

Oh, well, everytime i see it I think 'Oh shit... lost my conection AGAIN' because I usualy do.

Except when it causes the game to lag. Which is most times, for me.

Mine went over 300 mb

and I thought 180MB of it was high

Remove the game, download the client from www.guildwars.com
and install that.
It must download everything then

Well, I got it to like 25mb. But i have shit internet

if you do that, it's almost 1 gb of files...

As of two days ago, it was 1,016 MB...a few hours of downloading, but nothing terrible. Just let the client run minimized.