Please help me identifying these spaceship parts - big sloping ring

Question

Which lego set do these parts belong, I have a full box of random pieces, and I wish to build something starting from this. Thanks

Answer 1

It's from a LEGO UFO set from the late 1990s. You can see all the sets in this theme here: http://www.bricklink.com/catalogList.asp?catType=S&catString=34.311. What you have is most likely the #6975 Alien Avenger: http://www.bricklink.com/catalogItem.asp?S=6975-1