Of course Linux is more secure. It was developed by people who wanted a better way, not by people trying to make a buck.
Every time someone makes a new distro of Linux, they remove what proved to be unstable or insecure in the last one. Micro$oft, on the other hand, drags the same glitches and holes from on version to the next, and calls it "backward-compatibility". Just backwards if you ask me.
Had M$ started at ground zero and built Vista as a new OS... forget compatibility... I would have been impressed. Instead, they went their regular route to make it compatible. But Vista isn't. Stuff won't work with it. It should have come out in about another six months to let everyone else get their drivers and stuff ready.