I have Space Quest 1 (VGA remake...not available on GOG). But its been so long since I've had to tinker with DosBox (GOG spoils me!) that I have no idea what to do.

Who wants to give me step-by-step instructions & earn some positive rep?

GOG do provide a tweaked DOSBox as part of the install for their DOS games so you may not actually have much tinkering to do. I've only tried two DOS games from GOG so far and both ran perfectly fine out of the box with the pre-tweaked DOSBox included in the installer (Jagged Alliance: Deadly Games and Rise of the Triad: Dark War).

For starters you can just drag and drop the game's .exe on dosbox's icon, it'll load it directly.
After that you may need to adjust a few things.

Here's a config I use for the early King's Quest games. You'll probably have to make some adjustments to your own screen resolution and display mode.

Rename the file extension to .conf and place it in the game folder. In the exec section (the bottom), change the commands to what you'd do manually in DOSBox. Then, make a shortcut with the target as: "G:\Games\DOSBox\dosbox.exe" -conf dosboxKQ1.conf and have it start in the game's folder: "G:\Games\King's Quest Collection"

Or just use D-Fend. It really does make everything easier.

This works perfect for me...I grew up on DOS, but have since forgotten a great deal of it.

Only thing better than a GUI Front-End is a gooey chocolate chip cookie!

Its not DOSbox, but you can now play Space Quest 1 in SCUMMvm since it received a major update in October. I always found SCUMMvm to be easier to setup then DOSbox.