I had tried myself to install Linux using the MicroSolutions BackPack parallel CD-ROM drive. It is fully supported by Linux and I haven't had any major problem running it. Until version 2.0.36 it is supported by its own module (bpck.o) while in later versions it has been merged in the more general parallel port ide adaptors (the paride module that relays then of course on more specific low level drivers, which in the BackPack case is still called bpck.o).
In RedHat 5.x based installations the bpck module is available already at installation stage so you'll just have to select the BackPack cdrom from the Other CD-ROMs at the installation stage and then give it some more options (but autoprobe should work just fine).
In RedHat 6.x (which use 2.2.x kernels and should use then paride) the BackPack support was dropped. So to install the distribution from such device you will have to customize the bootdisk (adding the necessary modules) and the installation will be done without any problem.
Federico Pellegrin has customized a RedHat bootdisk that includes all the parallel CDROM devices that are supported by the distribution Linux kernel version (2.2.12) that should then work on all the supported parallel CDROM devices (even if he only tested it on his MicroSolutions BackPack since he doesn't have other simillar hardware). You can find some information on it and the bootdisk image at http://sole.infis.univ.trieste.it/~drzeus/rh_pcd.html.
As from RedHat 6.2 a supplementary driver disk was included in the distribution to support the paride devices. You'll just have to create the driver disk (the image file is paride.img and can be found in the images/drivers directory) in the usual way and insert it when the installer will ask for it.
Of course I suppose there isn't any problem in installing any other Linux distribution using such a device as long as you can add and configure the appropriate modules at the very beginning of the installation stage, but I haven't tested any.
You should take care of the mode the parallel port uses (ECP, EPP, Output only, PS/2) since some of them may cause your laptop to suddenly freeze or cause serious data corruption. On the other side some mode make the communication dramatically slow (I found the best choice on my laptop the PS/2, but you should make some tests).
This chapter is a courtesy of Federico Pellegrin. Please check also the CD-HOWTO.