OK, I thought I'd sort them by parts, 'cause I get emotional equally by all of them.
FFI: Uderwater Shrine(DoS) - It's just so beaytiful. I could almost feel shivers. Chaos Shrine(DoS) - Same here.
FFII: The Main Theme is just amazing! I liked the one from symphonic suite. It just sounded so epic with the chorals and everything.
FFIV: Rydia. It just fitted her character so well.
FFV: Sadness. The part where you-know-who dies... I actually cried!
FFVI: Terra (Piano Version)... Oh... I love this one... First FF tune I could play on my piano exam...
Spinach Rag just makes me all... floopy!
FFVII: Main Theme. The piano version is engenious.
Aerith theme... again... I cried at that fatefull moment...
FFX: To Zanarkand... Makes me think about sad stuff...
Suteki Da Ne... Love is in the air...
FFX-2: 1000 Words... ah....