Hi Susan,
Thanks for choosing Windows 8 and for providing us an opportunity to assist you.
No, you need not download a separate app to view the pictures from a CD. You have mentioned that you are able to view the pictures only one at a time. We’ll help you with this.
Just a few questions first to understand the issue better;
1) Which program\app are you using to view the pictures?
2) Which type of image files are you viewing? Is it a JPEG file?
If you are viewing the Picture from file explorer, then you can use the Windows Photo viewer option. Right click on the image file and select preview to view the image in Windows photo viewer. You can click on the next button at the bottom the Windows photo
viewer to navigate to the next picture.
You can also set the Windows Photo viewer as the default program to view pictures. Refer these links to set a program as the default program:
http://windows.microsoft.com/en-US/windows-8/set-program-access-computer-defaults
http://windows.microsoft.com/en-US/windows-8/choose-programs-windows-uses-default
Hope this helps. If you have any further queries, please get back to us and we would be happy to help.