Type C-h t to invoke the self-paced tutorial. Just typing C-h enters the help system. Starting with Emacs 22, the tutorial is available in many foreign languages such as French, German, Japanese, Russian, etc. Use M-x help-with-tutorial-spec-language <RET> to choose your language and start the tutorial.
Your system administrator may have changed C-h to act like <DEL> to deal with local keyboards. You can use M-x help-for-help instead to invoke help. To discover what key (if any) invokes help on your system, type M-x where-is <RET> help-for-help <RET>. This will print a comma-separated list of key sequences in the echo area. Ignore the last character in each key sequence listed. Each of the resulting key sequences (e.g., <F1> is common) invokes help.
Emacs help works best if it is invoked by a single key whose value
should be stored in the variable
Some Emacs slides and tutorials can be found at http://web.psung.name/emacs/.