A short list of frequently used shortcuts in blender.
Select a object : Right Click
Scale : S
Rotate : R
Grab/Translate : G
Duplicate an object : Ctrl + D
Delete an object : X (Displays the options for deletion in a pop up.)
F12 : Renders the Camera Perspective
Toggle selection of all items : A (this even selects the light and the camera)
After you dupicate, if you want to constrain the movement of the object to a particular axis relative to the original object, hold the X, Y or Z key while moving the mouse.
A Diagram of the all the shortcuts : http://wiki.blender.org/index.php/Doc:2.4/Reference/Hotkeys/Map
Go to Edit Object Mode : Tab (This renders the selected objects in the form of a mesh)
You can select and remove the keyframes for the currently selected object
Insert a keyframe : I
Remove Keyframe : Alt + I
Viewing
Center click and move the mouse : View Freely across the viewport
Shift center click and move the mouse : Translate the viewport view
Scroll : Zoom in / Out
Ctrl + Left / Right Arrow : Toggle between the different viewing modes.
References
http://wiki.blender.org/index.php/Doc:2.4/Reference/Hotkeys/All
http://www.katsbits.com/tutorials/blender/useful-keyboard-shortcuts.php
