raster - How to convert .geotiff --> .tiff?

How to convert .geotiff files to .tiff files (ordinary plain images)?

Basically, I have cropped the image to a rectangle of interest and knowing its left-lower location and having chosen the pixel size, I could combine several data sources as ordinary .tiffs (and could finally forget the tiresome ArcGis world..)

Any working method goes. We will employ usual image processing tools, and the location information is useless at that phase.

Thank you for any help! =)

UPDATE:

This is what I got when I tried to read GeoTiff in GIMP 2.8.4:

Answer

you can use gdal: (you can change PNG to JPG or TIFF too)

    for %i in (*.tif) do gdal_translate -of PNG -scale -co worldfile=no %i %~cnvt.png

i hope it helps you...