The timedLife boolean is to remove expiration timers.
I dont really know why the hell we want to use that but still.
The Positive/Negative booleans are pretty easy to understand.
When your target is happy, and positive is true, then it removes the buffs.
If your target is not happy and negative is true, it then removes the buffs.
In all other cases, it doesnt do shit.
(Or was it something else?)
The aura part is easy as well.
Auras are ussually not dispellable because you gain it when you are inside an aura... removing doesnt do shit as you re-gain it immediately... at least that is Blizzard logic.
The Physical and Magical part is something that is a bit too far into classifications.
For example, a buff like envenomed weapons is physical and a buff like inner fire is magical.
However, these are classifications of buffs which we all know that we can make a million more classifications if we want to.
Therefor it is pretty useless to use but they just implemented it.
Try make a test map with one unit being the target and one attacking it with envenomed spears (orc) and one buffing it with inner fire (human) and remove all buffs considered magical.
Poison stays, Inner Fire removed.
Try again removing physical buffs.
Inner Fire stays, Poison removed.
Also... "Remove all buffs considered Magical or Physical" vs "Remove all buffs considered Magical and Physical"... yea right.
EDIT:
But as I said, it is only classifications.
I for example would really much like a classification for Crowd Control.
Crowd Control is a classification of a buff that changes mobility (slow, stun, root, snare, knockback, taunt, etc)
I also want a level of a buff, for like removing all buffs lower than level 5.
Or I want a classification for stat changes (stat boost).
There are more than enough other classifications and shit to think about.
But the only two that exist in basic WC3 are Magical and Physical.
So for your actual question btdonald... dont try to make parameters for classifications in your buff system.
Try to make a way to add a condition function for it so map makers can make their own stuff.
At least that is what I assume that your question would have been.