If you are concerned about the format war consider the dual format options - Sony or NEC.
Fitting the drive is simple - three wires (all different so you can't get the wrong one in the wrong slot)
2. IDE (ribbon) cable
3. Sound (which connects to your soundcard)
and internal drives are VERY much cheaper than externals.
Writing 4.38Gb data (maximum that a 4.7Gb disk will hold) took me about 25minutes last week when I backed up "My documents" including music and photos (hence the file size).
This was using a minus format DVD-RW but I'm told (but haven't tried yet) that the plus format writes much quicker than the minus but is not as well supported by standalone DVD players.
Hope this helps