Let's start with some older sets I found.
The pirate set was most beloved and most expensive one for a long while. I should have all the parts to rebuild it but I think the sail is lost unfortunately.

The UFO I actually don't event remember owning, I must have been too little or it was a trade since we just traded legos all the time or something.

I loved castle and I believe I have many minifigs but this one was my biggest set. I was really envious of all my friends that had actual castles