For a Greek citizen: identity card or passport.
Yes
An identity card is sufficient.
The ID is sufficient.
No, you need a valid passport.
Yes.
No, you just need a national ID. Their both part of the EU.
No visa for the countries of the European Union: valid identity card or passport.
You need a passport or an ID.
As long as you are an EU citizen, you will not need a passport to travel to any EU country. As a Hungary resident, you can travel with only your ID to Greece from UK.
yes
Yes, you need a passport to travel to Europe.
Yes, you need a passport to travel to Paris.