Does my iMac support 5.1 Digital Speakers?

[iBunny]

?

Or am I stuck with analog?

[jsw]

It supports optical digital out, which means it'll support the speakers - as long as they or the receiver into which they are plugged support optical in.

[WildCowboy]

Yes, the combination headphone/optical port will run 5.1 sound.

[EricNau]

I started this thread (http://forums.macrumors.com/showthread.php?t=153911) awhile back, maybe it'll help you too. :)