Think of a regular Standard pack, but all non-Signature cards in it are Golden. That's what Golden Standard packs contain. They can drop Signatures where possible, yes.
Signatures in Golden packs are.... weird, because their odds are different depending upon which set they are:
Golden Standard have the same chances as regular packs for Signatures, 1 every 187 packs on average with a pity timer of 361.
Golden Festival of Legends have the same chances as a Golden Legendary in that set, 1 every 20 packs on average with a pity timer of 40.
Golden Match of the Lich King have greatly inflated odds, 1 every 7 packs on average with a pity timer of 14.
Think of a regular Standard pack, but all non-Signature cards in it are Golden. That's what Golden Standard packs contain. They can drop Signatures where possible, yes.
Signatures in Golden packs are.... weird, because their odds are different depending upon which set they are: