Things to Always Keep in Mind
Unlike the Macintosh PCs, Windows based machines are usually shipped with mice that have two buttons. The extra button, often referred to as the "Right Button" is immensely useful when you are looking for a way to do something. Windows, and other programs you may have installed, have put useful/commonly used items in the menu that appears when you right click on an object. The options that appear in this menu range from simple copy and pasting to giving you spelling suggesting in Microsoft Word.
Windows only allows you to have one program associated with any particular extension. Often though you may have several different programs that you use to open files (e.g. HTML files you might want to view in different browsers, or edit with a text editor). When you right-click on an object you will see an option titled "Open With..."; if you select this item, and proceed to select "Choose Program...", a window will open up and let you choose a program to open that type of file. Now, unless you select, "Always use the selected program to open this kind of file", this will not change the association this file type has, but that program will be added to the Open With... shortcut menu the next time you select that option. This allows you to quickly open files with a particular program without having to navigate the start menu, launch your program, and then opening your file.
Object Properties are Always Useful
At the bottom of the right-click menu is an option that appears called properties. This option is tremendously useful since you can change the way that objects look and behave, as well as being able to access many system settings such as the Display, System, Date and Time, and Taskbar and Start menu control panels. You can also change the permissions to files, file attributes, file details, and customization options.
<Ctrl>, <Shift>, and <Alt> When Dragging Files
Windows, by default, assumes what you would like to do with a file or folder when you drag it from one location to another. Windows generally assumes: 1) that you would like to copy a file when moving it from one volume to another, 2) that you would like to move a file when dragging it to a location on the same volume, and 3) that you would like to create a shortcut to a file when dragging an executable from one location to another. You can override these assumptions holding down the <Ctrl>, <Shift>, and <Alt> keys. Generally holding down <Ctrl> will copy your selection, <Shift> will move the file, and <Alt> will create a shortcut to that item. There is no need to memorize these keys since you can see the effect of your actions in the bottom right hand corner of your mouse. There is a symbol located there that will change as you push down keys. If nothing is there you are going to move the file, if you see a plus sign there you will be copying the file, and if you see a small arrow you will be creating a shortcut.
Paste (<Ctrl>-V) - In Windows you can paste anything that you have copied into the system buffer by using the Copy or Cut functions. This combination of keys is used when copying or moving files or text to different locations. The alternative would be to go to the Edit menu and choosing Paste.
Copy (<Ctrl> - C) - In Windows you can pretty much make a copy of anything, by pushing this combination of keys, let it be text, files, folders, etc. This feature is very useful for repeating text or for copying files to different locations when used. The alternative would be to constantly going to the Edit menu and choosing Copy.
Cut (<Ctrl>-X) - This feature is similar to the Copy shortcut except that this function removes the items that you have selected, hence there will no longer be a copy for you to go back to if you Copy something else before you Paste these items. This feature is really useful for moving files or text to different locations. The alternative would be to go to the Edit menu and choosing Cut.
Switch Window (<Alt>-<Tab>) - This feature allows you to quickly switch between windows and programs.
Properties (<Alt>-<Enter>) - Often you will want to look at properties for certain items in order to change the way that behave, look, etc. This shortcut will allow you to take a look those properties, or system settings.
Refresh (<F5>) - In Explorer windows, you can "refresh" the content you are viewing without having to utilize the menus. This is particularily nice for Web browsing, and if you are adding and removing files from a directory.
Bypass Recycle Bin (<Shift>-<Delete>) - If you are like me and are annoyed by constantly having to empty the Recycle Bin, then you can bypass the Recycle Bin by holding down shift when deleting a file.