1. You get to cast copies of both cards from one activation.
607.3. If, within a pair of linked abilities, one ability refers to a single object as “the exiled card,” “a card exiled with [this card],” or a similar phrase, and the other ability has exiled multiple cards (usually because it was copied), the ability refers to each of the exiled cards. If that ability asks for any information about the exiled card, such as a characteristic or converted mana cost, it gets multiple answers. If these answers are used to determine the value of a variable, the sum of the answers is used. If that ability performs any actions on the exiled card, it performs that action on each exiled card.
2. You can't imprint Ancestral Vision on Isochron Scepter because Ancestral Vision is a sorcery and Isochron Scepter only lets you exile an instant card. But if we take Evermind as an example then yes, this works. A card with no mana cost has a converted mana cost of 0, which is less than 2, and the fact that the Scepter has you cast the card without paying its mana cost circumvents the issue where you can't pay a mana cost that doesn't exist.
I'm not 100% sure on the first answer, so I will leave that one for someone else.
As for the second question, yes. Vision has a CMC that is less than 2 (0 is less than 2) and can be imprinted. When you activate the Scepter, it tells you to cast it without paying the mana cost which gets around the fact that it doesnt actually have a mana cost
W may only be paid with white mana. U may only be paid with blue mana. B may only be paid with black mana. R may only be paid with red mana. G may only be paid with green mana. C may only be paid with colorless mana. 1 may be paid with white, blue, black, red, green, or clolorless mana.
1) When you activate the ability, you can copy 0, 1, or 2 of the exiled cards. Both cards are considered "the exiled card" so the secon ability sees both when the ability is resolving. The last Gatherer Ruling on Strionic Resonator clears this up:
7/1/2013 In some cases involving linked abilities, an ability requires information about “the exiled card.” When this happens, the ability gets multiple answers. If these answers are being used to determine the value of a variable, the sum is used. For example, if Elite Arcanist’s enters-the-battlefield ability is copied, two cards are exiled. The value of X in the activation cost of Elite Arcanist’s other ability is the sum of the two cards’ converted mana costs. As the ability resolves, you create copies of both cards and can cast none, one, or both of the copies in any order.
2) Yes and no. Yes, you can imprint a spell with no mana cost and then cast it off Isochron Scepter. However, it still has to be an instant, which Ancestral Vision is not. The only one I am aware of is Evermind
1-What happens if I coppy the triggered imprint hability and exile more than one instant in the same Isochron Scepter (with a strionic resonator for example)
2-Can Isochron Scepter imprint and play cards with no converted mana costs? (Like Ancestral vision)
2. You can't imprint Ancestral Vision on Isochron Scepter because Ancestral Vision is a sorcery and Isochron Scepter only lets you exile an instant card. But if we take Evermind as an example then yes, this works. A card with no mana cost has a converted mana cost of 0, which is less than 2, and the fact that the Scepter has you cast the card without paying its mana cost circumvents the issue where you can't pay a mana cost that doesn't exist.
As for the second question, yes. Vision has a CMC that is less than 2 (0 is less than 2) and can be imprinted. When you activate the Scepter, it tells you to cast it without paying the mana cost which gets around the fact that it doesnt actually have a mana cost
2) Yes and no. Yes, you can imprint a spell with no mana cost and then cast it off Isochron Scepter. However, it still has to be an instant, which Ancestral Vision is not. The only one I am aware of is Evermind