I don't know much about the internal workings of the forum engine but As far as I've seen
If you click on the subscribed threads icon it will bring up a list of all the individual threads you have subscribed to in any major category . Just have to go through the list and select the one you want
Not 100% sure on the email notification but you can turn it on or off overall, not sure about individual subscribed threads apart from unsubscribing to them
Hanno or Keith would know far more on the options
