Scrolling: move your finger clockwise to scroll up, and counterclockwise to scroll down.
Select/OK: center button
Menu: goes back to previous page. hold menu to go to main menu. you may chose what items you want in this menu under settings > main menu.
Music playback screen:
to fast forward, hold '<< or >>' OR press center button once, and use the dial. clockwise to go forwards, counter to go back. when done, wait, and the diamond will dissapear.
song ratings: Hit center twice then use the dial to enter amount of stars. is saved to iTunes next sync
Shuffle: three center clicks. can shuffle by album, or song. if it is off, it plays the playlist in order.
lyrics (If applicable): four clicks in is where you can view lyrics. if you do not have lyrics for a song input from itunes, four clicks will bring you back to the main song bar.
volume: simply rotate finger clockwise (+ vol) or counterclockwise (- vol). no Center button needed. must be in music screen. (aka, now playing.)
Hold switch: while active (orange showing) buttons and scroll wheel are deactivated to prevent accidental key clicks and volume changes.
For reference and more information:
these are some very basics I have written, I can definitely answer any specific how-to-iPodclassic questions.