Header image and background colors won't appear

Two problems. I'd really appreciate any help!

1.
I created a header image in photoshop, making it about 1,000 pixels across and 150 pixels tall. I uploaded it into the atahualpa header images file (next to the one that was already there of the berries), but it won't display on the website. When I open the file straight from my cpanel it displays just fine. What gives?

2. When I use words to describe the background color I want (such as 'purple' or 'lavender') they show up just fine, but when I found some specific shades I liked and put in their number/letter codes, they don't display and it just stays white. What could I be doing wrong?