Convert MOV. to AVI.....fat chance!

Please, someone, somewhere must know of software that will convert a MOV. file to an AVI. or an mpeg with this damnable Vista operating system!

I have lost count of how many bits of software I have installed, tried, found seriously wanting and then had to uninstall, not so much as one so far has managed the job in hand, I've given up even trying for quality or options....anything will do!...though preferably freeware, I'm poor right now!

Help!