So lets get right into it...
First I'm going to use my D: drive on my main computer to create a folder which will be used as a mounted drive in Dosbox. You can name it whatever you want and can use any drive you wish its just that the D: drive is what I already used.
Next up were going to have to open the config folder for Dosbox. Press the start button and look for dosbox and click on "Dosbox 0.74 Options". A config file will open where you can modify settings for Dosbox. So we are going to scroll all the way to the bottom where you will see Autoexec.
We are going to mount the D:\dosgames with "mount C D:\dosgames" as seen in the config
Next were going to mount the CD-Rom cause you'll need that to either install or play games.
My CD-Rom drive letter is the F: drive where yours might be different. This is how you mount the cd-rom "mount d f: -t cdrom". Remember to save and exit.
Now you can open up Dosbox and you'll see that Z: is mounted this will happen every time. To change your drive letters to your selected mounted drives all you have to do is type the drive letters you selected. Example type C: for (D:\dosgames) and D: for (F: cdrom).
Remember to use dir /p to find out what directories you have on each drive. When selecting a specific folder use cd\ and the specific folder your going to open. Remember that if there is subs your going to need to use the full folder path. So example you have a game called bleep its folder name is bleep. You'll select this by typing cd\bleep and if it has a sub folder perhaps called sound you'd type cd\bleep\sound. Now you have access to that folder and files.
Okay so now you want to play a game but perhaps your video doesn't look that good so now were going to want to go back to "Dosbox 0.74 options" in the start up again. Change to what you see in the screenshot and it shouldn't look stretched with amazing picture. Remember to change the output to either OpenGL,OpenGLnb or direct 3d.