Is it possible to play old games in dosbox with internal speaker music, whether with real internal speakers or emulated speakers? Laptops don't have those old internal speakers so my only chance is to emulate it, right?

Does anyone know how to go about it, especially with games that don't have the "use PC speaker" as a sound option? I'd like to try some old games with that great beeping music, like Monkey Island and so on.

DOSBox (and ScummVM) emulate PC Speaker. Should the game support PC Speaker, the beeping music will be there.

How do you make it work though? I've tried one game which didn't have the option, yet it should be able to play the music via PC Speakers as I remember it working that way (Jazz Jackrabbit).

Same way it plays music if you choose Soundblaster, or Adlib. By sending the corresponding dos signal sound to your soundcard to play.
What music option did you select for Jazz Jackrabbit?

Sorry, I was thinking of Monkey Island 1 and wrote JJ because I've been trying out the shareware version again, you know how that happens sometimes. :)

I've uninstalled the games yesterday but I plan on taking a look at them later, from what I can remember though MI had Adlib, Sound Blaster, Roland, and two more - one of them might have been IB something, perhaps an IB speaker - was that it? Now I feel it might have been that but at the time the option didn't seem like it would be it.