Dimmer and pen color - newbie

I am learning from the trial version (CS), and I have been trying to
trace bitmaps, using the pen tool. I see how it goes, but, I am having
to go out of my way because I can't figure out how to do a couple of
things. One, how can I "dim" the bitmap (which I place in layer 1), so
that it appears very gray and white-ish, so I can clearly see my pen
points and lines as I proceed tracing. What I am having to do now, is
to first use Thumbs Plus to dim the bitmpap, save it, and then use this
dimmed bitmpat with Illustrator. Under Thumbs, there is a tab up top
with the name "IMAGE", and it has a rollout called "ADJUST", which lets
you adjust the brightness, contrast, gamma, colors, etc. I just adjust
the brightness and contrast to where I can still see the bitmap enough
to trace over it, but, very dimly so my pen marks will be clearly
visible. So, how can I just skip this THUMBS step, and get illustrator
to dim the bitmpa in layer 1 for me?
The second item is the color of the pen tool. I selected a new color
(an item on the lower right), but it doesn't change the color of the
pen tool. I want it to be black, but it keeps coming up red or blue.
I can never predict what color it will be - ?? So, how to force
illustrator to use a plain BLACK pen?
Otherwise, if you take your time, you can make a pretty good tracing
using the pen tool.
littleberry

Thankyou, Laura, do you mind another silly question? I can trace to my
heart's content, now, as long as i make it one long curved line (using
the pen tool). What I really need to do is to make a bunch of short
curved OPEN lines, where each line set is open, has many points, and I
need it to remain visible when I start another line set.
What happens to me when I try to "end" a line set (do you all call that
a "path"), is that when I start my next line set, the first one
dissappears on me? !!??! Blast. I can't figure this out. It would
seem so logical to me that I don't know why the help file is so
misleading. It says to select>deselect, but, that just makes my first
line set dissappear! If I can figure this out, then I can take a
complicated bitmap and trace a little here, a little more there, and so
forth, hiding the bitmap on and off as I go so I can see what my line
art rendering of the bitmap is looking like, and then, when I am
satisfied, I can save the line art. But I really just can't do it all
in one lone line set. I don't wnat to CLOSE the line set, because I am
viewing the whole bitmap as a bunch of short curved lines here and
there and I just want to have complete freedom over where I draw these
curved line sets (just like I would with a pen on tracing paper on top
of a printout of the bitmap.
Thanks if you don't mind giving me the clue I need to make multiple
curved line set that stay visible all the way. I am using layers, of
course, where the open the bitmap into layer 1, and then I create a new
layer 2, and that is where I deploy the pen tool, hiding and showing
layer 1 as I go. Littleberry