How do i make the background, on the bottom of my profile page around friends photo's ect, transparent?

It's the MODULE background - make it transparent. You must use a customized background in order to access the colors aspect. You can't adjust any of the pre-made backgrounds from Yahoo. So type the word - transparent - next to the module background field and click Save.

Click the "Edit Custom Theme" link toward the top left of your "My Page." Scroll down the image section of the pop-up window. You will see the sections regarding colors of text, modules and etc. (i.e. "Enter color hex value or click square to choose color.") As far as colors go, I copy and paste color codes from this site - http://www.december.com/html/spec/color.... . It's just faster that way. You can also type the word - transparent - instead of a color code, so that your background shows through. OR you can just click on the little box next to the right of the item, move the color scroll bar up and down, then click around in the color square with your mouse. You can click the transparent box there too. Using a custom background is an either or proposition. So, you must either a custom background and adjust what you can there or you'll have to use one of the Yahoo preset backgrounds, which you can't adjust beyond choosing one.