Is there a way to change the resolution used by the games that launch through dosbox?

Betrayal at Krondor is kind of squished-up in the fullscreen mode. I tried different graphics options and it didn't help.

The resolution of Betrayal at Krondor is fixed, so there's not a lot that you can do. In fullscreen mode, you probably have that black bar because the aspect ratio (width to height) is probably different than that of your monitor. Likely, the only thing you could do about that is play in windowed mode and stretch the DOSBox window to as close to fullscreen as you can get while still matching the game's aspect ratio.

As far as I know, there are no options - even undocumented ones - in DOSBox to help you change the resolution of a game to one that game engine itself doesn't support.

Bright side? You can play at 640x480 and have the window be small enough to simultaneously play two or three other DOSBox games! >.>

You might want to check your video card drivers for a fixed aspect ratio option so things don't get squished-up.

It's a dosbox option. Find dosboxSOMETHING.conf (go into game's directory and search *.conf, it should only give you one result), open the the conf file in notepad, find "aspect" under render section and change it to false. That should work, probably.

Alright! That worked great. Thanks man.