Tutorials
Linked below are the sources, there is a lot so I probably won't make a full example or anything just follow the same structure and it should work.
Browser & Windows XP
HTML
Right click page then click view page source to get the code then replace the content in browser-top, desktop, browser-frame, and os-taskbar with your own.
CSS
CSS SourceJS
JS Source (There's a lot of unrelated scripts here too)