Changing The Dock's Appearance From 3D to 2D?
Yes, you can, but only in OS X 10.8 or earlier.

You can use the the following Terminal command:

defaults write com.apple.dock no-glass -boolean YES &amp;&amp; killall -HUP Dock




To go back to 3D, run the following command (replace YES with NO):

defaults write com.apple.dock no-glass -boolean NO &amp;&amp; killall -HUP Dock