@shalmak

I would expect that a Vista machine should boot from a USB device.
You need to describe in more detail what your bios options are for
your boot sequence choices.

For example, I have a Win7 laptop with an hdd, several USB ports,
an SD Card slot and DVD/Recorder. My boot choices are HDD, DVD and
USB. The SD Card is only seen if one particular USB port is unused.

I have used Knoppix 6.2.1 on a 2G SD Card for about six months now,
and am really pleased with this setup.