Laptop setup

[jack]

I'd like to experiment setting up a laptop with a drive which is
completely encrypted.  I've worked with truecrypt in the past for
setting up particular volumes, and recently I've read (here) about an
encrypted filesystem available under Ubuntu.
I'm currently using Kubuntu 7.04, so I'd like not to destroy that disc
setup.
I have another laptop drive, and thought I might plug that drive into my
Kubuntu system as a usb, and install Xubuntu on it (flux is a smaller
lighter wm).  But, I think I'll run into a problem with fdisk.  Would it
be a wiser choice to install using the alternate install cd (I've never
used this) in order to be able to prepare the drive?  And, while for
security reasons I can see the merit in encrypting swap, is it wise to
encrypt the /boot partition?  I've heard that I can install a ramfs onto
a flash drive and create this setup, but I'm a little hazy on the
details of this.

Any input from the community, as always, is welcome.