In modern chinese, I would say 两百块钱 or 二百块钱。 二百钱 and 两百钱 are in classical chinese (wenyan)

More orally speaking, I would say 两百块/两百。钱 here is usually not spoken, since 块 (yuan) already indicates it is talking about money, 两百块钱 is also correct. In written Chinese, I will write 二百元钱 to be very formal.

I would have said "两百块钱"

Both, but 兩百 is used more.