To rename the file to a .rtf, you will first need to make sure that Hide Extensions is turned off. To do so, use the following steps:

1. Open your My Computer or My Documents folder.
2. Click on the Tools menu.
3. Click on Folder Options.
4. Click on the View tab.
5. Uncheck the box next to "Hide extensions for known file types".
6. Click OK.

With the setting unchecked, you should be able to see the .doc file extension on your document. Right click the document and click Rename. You will want to change just the last "doc" characters to "rtf".

Hope this helps.

-SW