Site Limitations

Whist making the site, I am finding various problems that I am finding hard to overcome, Some of which are not possible with my current HTML knowledge. One of these problems are with the background imagery. On the site I was inspired by, Pixelmess, they had different background images overlapping onto other divs, but I cannot figure out how to do this, so I have had to limit myself to one background per div. This also brings up the problem of different monitor sizes when it comes to making two background images link up, the images will look different on every screen. One way of solving this would be to have the backgrounds repeat on the x-axis, although this won't work for some as one end of an image will be linked with another.
The only way I have thought of overcoming this is to make very long versions of my background images. Although it takes up more space, I am pretty much guaranteed that these images will fit on any monitor size.

Another limitation was the amount of space I had for content. I didn't want the site to have a scrollbar, so I can't make the site too long. Therefore, I have to limit my space by using thumbnails with lightbox and sliders to fit all my content in a small space.