Dell Vostro 200
This turned out to be very unreliable. The best answer seemed to be to start over by installing Ubuntu 7.10.
Install Ubuntu 6.10 on Dell Vostro 200
CD-ROM not detected on installation
Go into BIOS (f2 when booting) and select "Integrated Peripherals". Find "SATA Mode". By default it is set to "IDE" -- change this to "RAID". That may not make sense, but this will allow Linux to see the CD-ROM.
Can't find network hardware
Download the Intel PRO/1000 Gigabit Ethernet drivers (a tar file with e1000 and igb drivers).