The general accepted god card vulnerability rule, as derived from the anime, is this (at least to my understanding):
Spell Card effects only last one turn, after which the effect is negated. The card is returned to its original state/position/ATK/DEF/etc. as it was before the Spell was activated. God cards are unaffected by the effects of Trap Cards. They can still be selected as the target of a Trap Card's effect, but it will not affect them in any way.
Magic planter
Yes, but make sure the counter trap card says it can counter a magic card (or whatever else you want to counter). Same for quick play spell cards, but mystical space typhoon wouldn't work because mystical space typhoon only says that it destroys 1 spell or trap card on the field. It does NOT say that it negates the effect.
Giant trunade. It is a spell or a magic that will return all spell and trap cards or all the magic or trap cards on the field
You are only allowed 11 cards as a maximum on a field, you have five monster card slots, five spell/trap slots, and a Field Spell Card slot.
No.
Yes, as long as the spell card is a Quickplay Spell, and the trap card is not a Counter Trap. So you cannot chain Monster Reborn to any trap. Nor can you chain Book of Moon to a Counter Trap, for example.
It destroys one magic or trap card on the field. It is chainable. *NOTE* It does NOT negate the effect of a spell or trap card. It destroys one Spell or Trap card on the field. This Spell or Trap card does not have to be one of your opponent's ones; it can be any Spell or Trap card on the Field. It is clearly stated in the text at the bottom of the card. Destroys 1 magic (spell) or trap card on the field. Really now.....don't be lazy.
Magic planter
Yes, but make sure the counter trap card says it can counter a magic card (or whatever else you want to counter). Same for quick play spell cards, but mystical space typhoon wouldn't work because mystical space typhoon only says that it destroys 1 spell or trap card on the field. It does NOT say that it negates the effect.
No, there isn't. Unless you count a Field Spell Card, which is a spell card but has its own zone, so technically you can have 6 spells active.
Giant trunade. It is a spell or a magic that will return all spell and trap cards or all the magic or trap cards on the field
You are only allowed 11 cards as a maximum on a field, you have five monster card slots, five spell/trap slots, and a Field Spell Card slot.
No.
magic trap and monster
Dust Tornado is a Normal Trap Card. It destroys one Spell or Trap Card on the field, then you can set 1 Spell or Trap Card.
You can't ever just discard cards for no reason, you can only do so if instructed to by a card effect or a game rule, such as the one that lets you replace one Field Spell Card with another.
Yes.