Comment 7 for bug 245399

This feature already exists in the alternate CD, which is great. For the desktop CD, the language could be very simple and not mention LVM snapshots or any other confusing concepts. When you boot to the desktop CD and start installing Ubuntu, the options could be:

Erase disk and install Ubuntu
Erase disk and install Ubuntu with whole disk encryption
Manual configuration (advanced)

The manual configuration partitioner should at least be as featureful as the alternate CD partitioner. When you create a new partition and choose the type, the list should include "physical volume for LVM" and "physical volume for encryption" as well as ext4, ext3, fat32, etc. Here is a screenshot I just found of an Ubuntu alternate CD (an older version) that does this: http://main.uab.edu/Sites/it/documents/63846.jpg

If you want to dual-boot Ubuntu and Windows, your partitioning scheme can look like this:

/dev/sda1 - NTFS for Windows
/dev/sda2 - ext4 for /boot
/dev/sda3 - physical volume for encryption volume

Within the encrypted volume you can set up a "physical volume for LVM" and within that create two volumes, one for swap and one ext4 for /. If someone already has Windows installed, Ubuntu can use free space on the drive to automatically create a /boot partition and put everything else in an encrypted partition.

In the Fedora Core installer, when you create a new partition there is a checkbox for "Encrypt this partition". When you check it, it prompts you for an encryption passphrase to use. This is a simple and straight-forward interface that doesn't make it any harder for people who are new to Linux to use, but it does make it much more secure.