i have come across a certyain person who is a judge saying that different cards can have their effect interupted by another card. 2 examples are playing last will and then suiciding your mother grizzly into your oppenant's monster. now this judge says that mother grizzly's effect is going off at the same time as last will's effect was going to go off. he says that two effects can't go off at the same time so last will's effect is negated because mother grizzly has priority. the second example happenned when this judge's oppenant summoned dark magician of chaos. he then activates ring of destruction to destroy the magician. he then states that his oppenant doesn't get the the magician's effect of getting a spell card from the graveyard because ring's effect negates the magician's effect. he said that this is a new rule, but i have not heard anything on it.

I'm not sure of the first one, but i think the turn player determines in what order they resolve. so grizzly can get its effect, THEN last turn resolves (same way necrofear gets her effect if destroyed if last turn is played)

but for the dmoc, dmoc is summoned and gets its effect, THEN is ringed.

"When this card is normal summoned successfully..."

he/she rings it after it's already been summoned to the field, as ring does not negate the summon (same with trap hole, bottomless trap hole, etc.)...that's successful. you get a spell card from your graveyard.

Ring of Destruction doesn't negate the summon of DMoC so it WOULD still get its effect.

With your last will question I would say that you would get both effects. I have heard nothing about that two effect at the same time thing.

The last will question. They don't activate at the same time. Mother Grizzly activates as chain link 1. Last will is waiting for the current chain to resolve so it can start a new one. Other occurances when this kinda thing happens is when airknight attacks a face down cyber/fiber jar. The jars effect can't interrupt the current chain of airknight drawing so it waits until it can start a new chain. See what I'm Saying?

ok, now the last will question has to do with SEGOC (simultaneous effects go on chains). this is when 2 effects are triggered and attempt to activate at the same time. when this happens SEGOC forces them to form a chain.

the turn player gets to put one of their simultaneous effects as link one, then the opponent etc. in this case both last will and the grizzly are the turn players cards, and so he gets to decide what order they chain (and resolve). so you will get both effects.

now, as for the dark magician of chaos, this has to do with the optional triggers and loosing timing rule. which says that an optional trigger can only be activated if it is the last action to have occured (in other words it didn't happen in mid chain/effect). but in this case you summon DMoC, then his effect attempts to trigger, since the trigger (summon) was the last action, you may trigger it, then the opponent can chain RoD to the effect to destroy the magician, but the magicians effect still works, since it was not negated.