A quick way to improve working with your computer is to use keyboard shortcuts. They save clicks and can speed up the process by eliminating switching between keyboard and mouse. There are some that I use on a daily basis:
Tab (cycle through fields)
Shift+Tab (cycle backwards through fields)
Shift + Arrow key = Highlight text/objects in that direction
Windows key = Open Start Menu
Ctrl + Esc = Open Start Menu
Windows+L (Lock the computer)
Windows+M (Minimize all windows)
Windows+E (Opens My Computer)
Windows+B (Focus goes down to System Tray)
Windows+Pause = System Properties (same as right-click My Computer, Properties)
Alt+Tab = Cycle Windows
Ctrl + Tab = Cycle Tabs (in Firefox)
Ctrl + C = Copy
Ctrl + X = Cut
Ctrl + V = Paste
Ctrl + A = Select All
Ctrl + B = Bold
Ctrl + F = Find
Ctrl + Z = Undo
Ctrl + Y = Redo
Ctrl + P = Print
Ctrl + O = Open
Ctrl + E = Center (in word processors)
Ctrl + I = Italicize (in word processors)
Ctrl + U = Underline (in word processors)
F2 = Rename a file
F3 = Find Next
Alt+F4 = Close window
Ctrl + F4 = Close tab (in Firefox)
F5 = Refresh
F8 = Get into Safe Mode when booting into Windows
F10 = Access most BIOS at boot-up
F11 = Full-screen for IE/Firefox
Print Screen = Screenshot of the desktop
Alt + Print Screen = Screenshot of the active window
Home = Top of the page for browsers/beginning of sentence in word processor
End = Bottom of the page for browsers/end of sentence in word processor