Snow Leopard's Preview application has scale-to-fit and auto-rotation enabled in the Print dialog by default, but it doesn't seem to retain changes to these settings between restarts when I disable them in GUI. To change these settings permanently, copy and paste these commands into Terminal:
$ defaults write com.apple.Preview PVImagePrintingScaleMode 0 $ defaults write com.apple.Preview PVImagePrintingAutoRotate 0
Mac OS X Hints
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