Problem with Lemmings
 

First off I do have DosBox 0.63 and I am trying to play Lemmings (downloaded from here) in DosBox 0.63 and when I press F1 to play single player, it brings up the screen of what I need to do in order to complete the mission, I press spacebar to continue, and then the screen goes black and nothing more happens.

Also, I am using the command, Lemmings, to start the program.

0.63 is outdated for three years.
Each version of DOSBox has a number of compatibility fixes for known issues with games/software in the preceeding one - hence games that don't work so well (or at all) with an old version could run just fine if you use a newer one.
Both speed and stability of emulation has greatly improved since 0.63 as well, so I suggest you get a more up-to-date version (0.72 is the newest around).

That was the problem alright. I guess my problem is that I had gotten Dosbox 0.65 not shortly after 0.63, and I had a ton of problems with 0.65, however I didn't think it'd be up to 0.72 by now. Thanks for the help :)

Ya 0.63 is way outdated. 0.72 might have what ever problem you are having fixed.

Starting game
 

First of all thank you for posting the game The lemmings, i have been looking for it for over 3 years. It's a childhood memory.
My problem is when in dosbox i see C:\L3 i can not run the game...
it won't start so i cant play!!!
Please help me!

And how exactly did you attempt to start it?

I typed FB

wait, exactly which version of lemmings are you running? link please

and why did you type in "FB"? did you use dir command before?

http://www.abandonia.com/en/games/23...es%2C+The.html

I typed DIR
then I saw what was in the folder
c:\L3:
then I typed FB

It must be L3 or L3F .....
[Edit]
Added screenshot of what you must see when you're mounted L3 right and are in the correct directory.