[SOLVED] Static background image for page menu bar

I can't find any information on this. I hope I explain it right. My issue is:

I want the background of the Page Menu Bar to one background, no border, and transparent backgrounds (no border) for the categories.

So basically I want a bar, just like bar1 or bar2, but with one static background image, that's behind all menu items.

I would also like for my menu to start about 100px (or more) further from the left side of the site.

Would anyone be able to explain to me how to do this? Which files, which part of the code?

Thanks in advance.