You can boot directly into the console if you wish, but you're stuck with no (easy) way to start Aqua. So there's really not much point unless you like the console.
If you really want to, edit /etc/ttys
There's a line near the top that looks like this:
# console "/usr/libexec/getty std.9600" vt100 on secure
Delete the # character from in front of it.
Then the next line looks like this:
console "/System/Library/CoreServices/loginwindow.app/loginwindow" vt100 on secure window=/System/Library/CoreServices/WindowServer onoption="/usr/libexec/getty std.9600"
Place a # character in front of it. Then save the file.
The next time you boot, you will boot directly into the console.
Apple didn't really make provision to do this one, so the screen will stay that nice gray color. You'll get some text saying "Welcome to Darwin" and under it "login:" that will be white text on black, but the rest of the screen will be totally gray. Once you login, you can either type reset or clear and the whole screen will go black.
You could also hold down command-v to start in Verbose mode, then you don't have to worry about the gray screen.
But there's still no easy way of starting up Aqua. You can't just run the two apps from the line above; I tried that and almost hosed my login window! So I wouldn't suggest trying it. It took me a couple of hours to get it back to working normal (though I must admit, I had done some other things at the same time, and it could have been one of the others that did this...but still, I thought I would warn you guys).
Oh, another thing if you start up your machine holding down command-s, you start up your machine in "Single User Mode" where you also can continue the restart if you wish. I don't know how this is different from "Verbose Mode" (command-v) though
Single User mode automatically logs you into the console as root. I patched my kernel to stop this from happening. It's a very serious local security hole, if you have a reason to worry about that for some reason or another...
-I hope by now you've found the answer but if not here's how to exit out of xwindows when aqua is NOT running. In other words, if you've already booted normal, and started xwindows using Xdarwin (either fullscreen or rootless) you logout by typing logout at an xwindows terminal, or choosing it from a menu, or quiting xdarwin, etc.
If you login through >console, and aqua is NOT running, you logout by choosing it from a menu, or typing logout at a terminal prompt.
type exit or logout again when you've got the spinning technicolor pizza of doom. That will send you back to the nice, pretty, aquified login screen. Then login again as >console.
Hm. I think this is the other way 'round, though. (Just to clear this up.) This thread was probably moved to the HOWTO section, as originally intended. You post a question to the OS or other specific forum, and if a solution arises, this would then become a HOWTO. But I guess I inadvertently revived this thread yet again for no proper reason.