Curt,
Thank you for your business first of all. Let me see if I can help you out.
Your best bet would be to size your images before you upload them. WordPress will attempt to make them fit, but if you can edit/crop them before uploading, you’ll have the best control over the final result.
Here are the image sizes for the home page slideshow. If you’re using the option without the top sidebar, the image size is 960 pixels wide by 400 pixels tall.
If you’re using either the sidebar or the static layout, then the images are sized to be 608 pixels wide by 403 pixels tall.
If your image is larger than those sizes, WordPress will scale them down, but won’t scale them up. It will also stop scaling down, once it reaches either the specified height or width.
I hope that helps out. If you still have trouble, let me know and if possible, send a link to where you’re working with the theme and I’ll take a closer look for you.
Enjoy your weekend,
Bill