Far as i know it all goes by the circuitry and hardware inside your firewire case. If it has newer oxford or nec drivers then it should recognize 200 gig h drive. You wont know til you try.
I have heard that one can flash the oxford drive inside the case it its oxford but i have never done it. You can likely google the info on that. AGain, you might just as well try it first. There is a barrier at 130 something, some cases with newer oxford or nec will read the drive size right, older ones wont.
How would you connect a firewire external drive enclosure to an ata controller card, only way would be if you could buy an ata controller with a firewire connector on it, which i dont think exists, yet.