i would greatly reccomend the floppix labs ( http://floppix.com/labs.html )
Floppix is a linux distribution on two floppies, intended to teach linux in comandline only mode. it is some 37 separate labs with questions and so, must be made by a teacher, it is a good way to start.

below i have listed a few linux=DOS equivalents.
dir /w = ls
dir = ls -l
add an a to list hidden files (ls -al). in linux anything named with a . first is a hidden file (.file).
copy file /new/file = cp /file /new/file
del =rm
add -r after (rm -r) and you will empty everything below that searchpath. add -f and you force the removal.
rm -rf / erases everything on compuer that you have read/write access to, as root that is EVERYTHING.
rmdir removes a directory (must be empty)
mv moves and/or renames a file mv /file /file2 renames the file. mv /file /new/file moves it to directory /new and finaly mv /file /new/file2 moves AND renames the file.
keep asking.

btw the man mv gives more, so does mv -h and mv --help and aporpos mv
to list available comands do ls on these directories,
/bin
/usr/bin
/usr/local/bin
/usr/X11R6/bin

now to list the comands available as root (root, the almighty superuser,aka 0.0 in linux/unix, more powerfull than any admin in windows)
/sbin
/usr/sbin
/usr/local/sbin
there are more but tese are confusing enough for now (as you see directories with bin in them are full of comands)

if the lists become too long you can pipe the output to less.
ls /usr/bin|less

to navigate use upp and down arows OR pageup/pagedown.
here to help
OE