Print "Actual" Size

Problem: You want a picture to print out to an exact size (in my case I wanted it to match another printed picture which was not of standard size) but when you print it only lets you print at standard picture sizes e.g. Photo, A4, A3 etc. (had this problem while using Paint.NET, a great program, and Windows... though the problem I think is more Windows related than Paint.NET).

Solution: Set your canvas size to a regular size that is larger than your image e.g. A4, A3 etc, then paste your image into the centre of that canvas. When printing choose output size that matches your canvas and be careful not to choose the "Fit to page" setting.  This worked for me.  Would be great if Microsoft just supported "Print actual size" (go figure!).