...and... there's a way to make the spawner reset after a time period?
i did a spawner actived from the use of spirit speak skill, but i want that the spawned monsters will be delated after 5 minutes... i think that its possible, but i don't know how to do it
any suggestion?

set the Duration property on the spawner to the length of time that you want the spawns to last. After that amount of time has passed from the time they were spawned they will be removed.

I have another question:
How can i set a delay between 2 trigger?
I tried to create a spawn that is activated only if the player have a certain item on the backpack... If the player have the item then an escortable will be spawned, and it works correctly... But when the player accept the escort, the spawn immediatly restart the trigger and respawn another escortable (its bad to see 2 identic npcs in a quest ).

Im sorry for my very bad english, il do my best to let you understand what i mean!

You can set the refractmin/refractmax time. That sets the minimum interval that the spawner has to wait after being trigger before it can be triggered again.