If you can open the document in an application that can "print" the document, then you can turn that document into any of these file formats:
However, I hesitate to suggest PDFCreator...
...because it is a pain to prevent extra junk/features from installing.
Download PDFCreator 1.7.2 - FileHippo.com
If you will follow these screenshots, then you should be safe on the installation:
Select Run or Save or Save as...
Deal with the User Account Control and OS security windows - if need be.
(not shown via screenshots)
Remove every check - except the ones shown in the next two screenshots:
After you click on
Install (as shown above)...
...you may be offered junk (as shown below):

I have moved the window to show you that this offer of junk is via a separate installer with its own window. Just click on
Cancel to decline the junk. The other installer should continue.
Uncheck the option to
Show help after setup.
Now you are ready to "print" to jpg.
Open the RTF document in any app that can print.
You do not have to use WordPad like I do in these screenshots.
You only need to do this step one time:
You only need to do this step one time:
Edit:
If you are going to print lots of documents, then it is worth your time to learn how to use the auto-save (batch-print) feature:
