I am trying to record the first game of Space Quest in DOS Box so that I can upload it to Youtube. It is the first game that i have recorded that slows down during recording. Is there a way to fix the lag? I cannot use my DOS Box installed to the computer because SQ.COM doesn't seem to work when I try to execute it. This must have to do with the extension name. Space quest 2 would then be the same, and Space Quest 3 uses SCIV.EXE so it would work.

Try to increase DOSBox cycles - press CTRL-F12 (CTRL-F11 to decrease). You can do this repeatedly, but you will be limited by the power of one core of your CPU.

The version of Dos Box that GOG.com gave me puts the CPU cycles to max. I can't make it better than that.

I'm trying to put it in my computer's version of Dos Box.

If it's already at max, try to decrease CPU cycles - CTRL-F11.