Starfire glass is a low iron glass, it is supposed to get you a better clarity when looking at things inside the tank
Drilled holes are for overlfows - which allows you to run a sump in the stand of the tank (or in the basement if you really get crazy). You do not need a sump for a saltwater tank, but it is a great place for things like heaters and thermometers and all kinds of other stuff that would otherwise be in the tank or hanging off the back / side
As far as filtration goes - in saltwater it consists of 1-2 pounds of live rock per gallon, and a good protein skimmer. Undergravel filters are an ancient technology, and you;ll find that most saltwater enthusiasts no longer use them.
If you're not in any hurry to get this going (and if you are, I urge you to reconsider) and I would go pick up a copy of The Conscientious Marine Aquarist by Robert Fenner. Its pretty much the bible of saltwater. While some of the info is dated, its all still valid. I've ready it cover to cover about 6 times now, and i still find myself referring to it occasionally. Robert Fenner is also part of a website called Wet Web Media. There are a lot of articles and FAQ's there as well.
Those of us here at Living Reefs are also happy to answer any questions you have