That is a small forum factor PC. While it came with a DVD as an option, it seems unless you buy the unit expressly made for the SFF case, it would be much easier to use an external drive. If you do buy the internal, here is how you install it.
High speed USB (2.0) would give you close to internal speeds, so assuming you do not want to go the internal route, I see no real reason to be concerned.
I have a 2005 Dell Dimension 5150C with Windows XP . It has a CDRW/DVD drive (Philips SCB5265). I want to get a DVD writer & am not sure if I should get an external or internal writer. Which is best? Which is easiest? And which do you recommend? Please, please help me.