I've been putting AutoText entries, keyboard shortcuts, and custom toolbars and menus in Normal.dot so that they're available to all my documents. But I've had to delete and rebuild Normal.dot twice in the last couple of months, which was a huge waste of time.
When Normal.dot gets cranky, Word's foundations start to quiver.
Your first line of defense is to back up Normal.dot often, so that even if it does get corrupted, you can recover quickly using an older version. But if Normal.dot is starting to corrupt frequently, you're probably keeping too much information in it, so you should transfer as much as possible of that information into other locations.
Create a new template and save it. With the template still open, choose Tools » Macro » Macros, and click the Organizer button. Use the controls on the Organizer dialog box's four tabs to move the AutoText entries, keyboard shortcuts, and custom toolbars and menus to the new template. Save the template and close it.
Still in Word, choose Tools » Templates and Add-Ins, click the Add button, navigate to and select the template, and then click the OK button to load it as a global template. Back up this global template frequently as well, in case it too sustains corruption.
You can load the global template automatically, if you prefer, by placing it in your Word Startup folder. Choose Start » Run, type
%userprofile%\Application Data\Microsoft\Word\Startup, and press Enter to open a Windows Explorer window to your Word Startup folder.