Paint.NET is a freely available image editing program that you can get here. It's not as powerful as something like Adobe PhotoShop or Corel Paint Shop Pro but it does include the basics of image editing. More importantly for us, a comprehensive benchmark is available for it, which runs a multitude of operations like resizing, applying filters, and cropping in quick succession and times how long they take. For more information on the benchmark you can read this thread on the Paint.NET forums.
There's not much one can say about this result. It's quite clear that when it comes to image processing speed it matters not which OS you use.
Handbrake is one of the simplest and slickest video encoding tools available on the market and, like Paint.NET, it's free. For our testing we encode a two minute eight second video clip shot at 1080p and stored in MPEG2 into an iPhone friendly format, i.e. an mp4 file encoded in h.264 and resized to a resolution of 480 x 320. The time to completion can be found in the programs log file and this is what we report.
This test shows a more discernable difference betwen the three OS's with Windows 7 coming out worst. However, the difference only actually equates to a five per cent swing.