Logging on to Linux via X

[Robert M. Woods]

Hi Linux People,
  I'm getting a little more familiar with X thanks to a lot of you..  I was
wondering though, is there a way I can boot up Linux to a graphical
interface?  For example, have a graphical login prompt rather than the
terminal line login prompt??  I would guess I would need to change the run
level of something, but what??
  Also, is there anyone into Tcl/TK??  Just curious, I recently acquired a
nice package, Visual Tck/Tk..  I like this language even more than java!
  Rob.