One alternative: http://apcmag.com/how_to_dualboot_vista_wi...screenshots.htm
<<Would I be better off using 3rd party software to Create an unused Partition.>>
I wouldn't necessarily say "better off", they are alternatives to getting the same task accomplished, IMO. Since I have had partioning software for some time, I probably would use that. If I didn't have such already, I would try the suggestions/procedures depicted in the first link above.
The fact that Vista has partitioning capabilities which XP did/does not have...might alter my decision to acquire partitioning software today...such tools were not inherent in Windows back when I first acquired the software program I use for such.
I also just read that Partition Magic (the program that I use with XP) does not work with Vista, so that would influence any decision I made relative to partition software today.http://www.vistarewired.com/2007/02/16/how...n-windows-vista