Conversion to Linux

OK, now the real reason for joining KCLUG - I am looking for information and wisdom. The company that I work for is contemplating a major shift from Microsoft to Linux within the next year or so. I am pretty much the only Linux-savvy guy here, and that isn't saying much. I have messed around with Ubuntu, Linspire, and a few other distros, and Ubuntu is wowing the executives right now with its ability to access windows shares, etc. - they want me to draw up a rough plan of what it would take to switch to linux in a gradual way. I am looking for some help and guidance, please no flame wars...

Michael Haworth