In config file:
aspect=true

optionally you can also set
fullresolution=0x0
output=ddraw

I hate to sound really dim but how do you edit the config file?

I can't even find the darn thing. It's not in the folder where dosbox is located. I'm using Vista if it's of any help.

Start menu => DOSBox => Configuration => Edit Configuration

Hmmm...Dosbox actually got installed on my computer because it came "bundled" with Red Baron so it isn't present in my start menu. Is there any other way to get to the configuration file?

0.72 and previous: config file is where dosbox.exe is. 0.73: config file is in \usersdirectory\username\local settings\application data\dosbox

where userdirectory is either "Documents and settings" for WinXP and "Users" for Vista and I think Win7. I have three config files there and I don't know which one is used (I've put a dosbox.conf file in the same directory as dosbox.exe).

Well, I don't appear to have a local settings folder in my Users/username/ folder.

What is the config file actually called? I can try to find it using search.

Scratch that - it appears there IS a folder called AppData in my username folder. However, I can't seem to see it. Is there a setting in properties that I need to tweak to make it visible?

install latest official dosbox and reset configuration.

Same place it's been since Windows 2000:

Computer-Tools->View->Show Hidden Files and Folders.

Also you don't really need to see it, you can still access it without seeing it by just pasting Appdata into the path
ex: C:\users\USERNAME\PUT APPDATA HERE

Hi, everyone.

Thank you for all your help. I managed to finally edit the dosbox.config file using the parameters given earlier in this thread and...I still have the black bar at the bottom of the screen!

🙁

Try output=overlay or output=opengl. If they don't work, I can't think of anything else.

Unfortunately, neither of those worked.

Thank you for the help, though. I'll try fiddling around with this on my own.

Thank you everyone for your help.

I figured it out.

Basically, I was running my game (Red Baron) by clicking on an icon which was on my desk-top; checking the properties of that icon, it turned out that not only was it calling up dosbox, it was calling up a specific dosbox.conf file which was specific to Red Baron; thus, all the changes I'd been making on the default dosbox.conf file were made in vain!