Most notebooks today come with CD drives. If floppy and CD drive are swappable they are usually mutually exclusive, however many vendors (HP, Dell) provide cables which allow the floppy module to be connected to the parallel port. Sometimes the CD drives comes as external PCMCIA device (e.g. SONY), or as SCSI device (e.g. HP OmniBook 800), USB device (e.g. SONY), or as Firewire (e.g. SONY VAIO VX71P). Such an external devices might bear problems to install Linux from it.
As far as I know there are SONY DiscMans available which have a port to connect them to a computer or even a SCSI port. I found an article published by Ziff-Davis Publishing Company (September 1996 issue, but missed to note the URL) written by Mitt Jones: "Portable PC Card CD-ROM drives transform laptops into mobile multimedia machines", which listed: Altec Lansing AMC2000 Portable Multimedia CD-ROM Center; Axonix ProMedia 6XR; CMS PlatinumPortable; EXP CDS420 Multimedia Kit; H45 QuickPCMCIA CD; Liberty 115CD; Panasonic KXL-D740; Sony PRD-250WN CD-ROM Discman.
To here music from internal CD drives usually works without problems. But note:
Some notebooks come with an external CD drive, you need an extra cable to connect the sound output of the drive to the sound input of the notebook.
Most notebooks today even come with internal or external CD writers. The internal usually work, see CD-Writing-HOWTO for details. But with the different external (PCMCIA, Firewire, USB) drives you probably need some tweaking.
regionset adjusts and shows the region code of DVD drives.
Universal Disk Format (UDF) Driver : "UDF is a newer CDROM filesystem standard that's required for DVD roms. It's meant to be a replacement for the ISO9660 filesystem used on today's CDROMs, but the immediate impact for most will be DVD. DVD multimedia cdroms use the UDF filesystem to contain MPEG audio and video streams. To access DVD cdroms you would need a DVD cdrom drive, the kernel driver for the cdrom drive, some kind of MPEG video support, and a UDF filesystem driver (like this one). Some DVD cdroms may contain both UDF filesystems and ISO9660 filesystems. In that case, you could get by without UDF support."
DVD formats:
Digital Versatile Disc DVD-5 4.4GB 1side 1 coat ~ 2h video DVD-9 8.5GB 1side 2 coat ~ 4h video DVD-10 9.4GB 2side 1 coat ~ 4.5h video DVD-18 17 GB 2side 2 coat ~ 8h video