How to Delete Words with Single Keystroke
This is a great shortcut.  While working in Word we all make mistakes and need to delete stuff. Normally you just select the text and press DELETE, while others may simply hold down the DELETE or BACKSPACE keys until the unwanted characters disappear.
If you are in the latter group, and you spend a lot of time pressing DELETE or BACKSPACE, you may be interested in a handy shortcut provided by Word. All you need to do is hold down the CTRL key to speed this up. Using CTRL+DELETE deletes text from the insertion point to the end of the next word. For instance, if you wanted to delete four words to the right, simply press CTRL+DELETE four times. Likewise, CTRL+BACKSPACE deletes words to the left of the insertion point.  You don't even have to take your hand off the keyboard to do this. Just use the arrow keys to position the cursor where you want it and hit CTRL+BACKSPACE or CTRL+DELETE, and the words are gone
A great use for this is if you only need to delete the first or last half of a word.  For instance, let's say you wanted to change the word "sidestep" to "sideways." Normally you would find some way to simply delete "step" and type "ways." This could involve pressing DELETE or BACKSPACE four times to get rid of the unwanted portion of the word. You can make your edit faster if you just position the insertion point at the beginning of "step," press CTRL+DELETE once, and then type "ways."

How to Preview a Document in Word 2007 without Opening It.
If you have a lot of Word documents and are not sure which one contains the information you need, Microsoft Word 2007 allows you to preview a document within Word without having to open each document.
Open Word and click on the Microsoft Office Button and choose Open.
The Open Dialog box will appear.  On the right hand side of the toolbar click the down arrow on views and choose Preview.
This will open the preview pane.  Click on any file on the left hand side and preview what inside the file.  When you find the file you need just click Open.

Insert vs. Overwrite In Word
Take a look at the status bar at the bottom of the Word document window. If you see the letters OVR in bold type on the status bar, the problem is that you have inadvertently hit the INSERT key as you were typing. When you do, Word enters a special editing mode known as "overtype mode" (that's what the OVR characters stand for). While in overtype mode, everything you type replaces something else in your document. For instance, when you type a letter, it replaces the letter to the right of the insertion point. When overtype mode is not active, your text is inserted where the insertion point is located.
To undo your messed-up document, first turn off overtype mode by pressing the INSERT key again. (The OVR characters on the status bar should no longer be bold.) Then, press CTRL+Z to undo your last edit. You can continue to press CTRL+Z until all the characters you inadvertently overtyped are again within your document. Now you can go ahead and continue typing without overtyping your original text.