Because of the wording I am not exactly sure what you are asking but you can install some Linux distros directly without using anything else. Yellow Dog, Fedora, SuSE then you just dual boot.
I am running slackware 12 and debian etch on Parallels without any issues, so you should be safe to go that way. If you want to dual boot, you may want to check out this site:
Mac Specs: Blackbook - 2.0ghz Core Duo - OS X 10.6 - 100GB HDD - 2 GB RAM: iPhone 3G S, 32GB
Most Linux distros will work with Parallels. I use SuSE and have also tried Debian and Ubuntu. Getting the resolution to the native notebook resolution was a pain in Ubuntu for reasons I can't fathom, but was fine in the other distros.
As someone said, there is no need to use Bootcamp because most Linux distros will partition things themselves, BUT if you're under Apple Care or Warranty, you should use Parallels, VM Fusion or Bootcamp, because otherwise if your HDD craps out, you might not get helped.
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In the land of the blind, the one-eyed man is stoned to death.
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