By desktop you probably mean the wallpaper and icons. You need iconpackager for the icons. You might find a link to the wall in the comments of that particular skin.
The start menu probably is windowblinds, as f0r3 said. Make sure you have WinXP or you will need Objectbar in addition to windowblinds, if you have Win98 or WinME.
It all may sound a little complicated, but a little patience is all it takes. Remember, Rome wasn't built in a day. You can find shareware versions of Windowblinds and probably Iconpackager on the left of the website under Resources and Software. If you decide to pay for Object Desktop, you will have everything thing you need. Good luck.