Well, you (most probably) do have a bunch of terminals ready for you - just press Ctrl+Alt+Fx, where x is 1 through 6. To get back to the X server, where KDE is, press Ctrl+Alt+F7. Anyway, if you want to stop it from booting directly to KDE (or whatever), check your /etc/inittab. You'll see a line there, which looks like something this:
Change the 5 to a 3 and it won't start the X server. To start it from the console, type init 5
or maybe startx
If you want to boot directly to a bash prompt and nothing else (possibly to save a damaged system), append init=/bin/bash
to the boot prompt before booting the system.