Miscellaneous Website Tweaks

I have a website mostly created through WordPress but need a few tweaks to the template. I need the background changed from a repeat-y image to a single static image (potentially dynamic based on screen resolution?). This image should not scroll with the body content of the page. I also need the background of the content section to be about 30% transparent, revealing the background image. I also have a jQuery slider script for a few images that needs to be added to one of the pages. I may have a few other miscellaneous tweaks along the way but those are the basics.