Well, it's time for me to show my true colors and join Dagoth Ur. I have heard countless praise about this mod until I went and looked it up...and there are tons of them. Which one is generally considered the best?

Tons?

There are only two large ones that have a full questline for joining the House. (that I know of)
http://planetelderscrolls.gamespy.com/View.php?view=Mods.Detail&id=801
and
http://planetelderscrolls.gamespy.com/View.php?view=Mods.Detail&id=2464 - http://mw.modhistory.com/download--7126

Both are really good, but obviously not compatible.

There's also the http://planetelderscrolls.gamespy.com/View.php?view=Mods.Detail&id=7141