Kristi,
Your biggest issue in the page scrolling left and right in the browser is due to your image sizes, I would imagne you have a large viewing resolution set in your monitor.
Your buttons are 225 pixel width and you have 5, so your total pixel width is going to be 1125 pixels. This will cause scrolling in 800x600 and 1024x760 resolutions.
Your large picture is 1280 pixels, causing the same issue as your buttons.
Your Mom may be seeing black because she clicked a hyperlink. You are using the default colors of links being blue and visited links being a dark purple, but your mom may be seeing that as black.
The best way to stop right / left scrolling will be to resize your images and then resample them.
Go to File > Preview in browser> and view different resolutions to see how your site will look.
Your in "JUMBO" size now

), so it will probably look quite a bit different on your monitor if you resize the images.