Double posting is usually frowned upon in this forum, and the replies wont be instant.
Here is an easy way to start it up. Click on the start button, then click on the run button. Then you type mspaint and click ok. Now you should be running MS Paint, also known as Paint.
If you plan on making a character wad, its recommended that you actually know how to draw. It takes more then 100 frames for the wad to work, and people want quality rather then quick ms paint edits.