Mine is probably Super Mario Land Invincibility Theme (Can-Can) I've heard it so many times, and it's so catchy.
anything in shadow hearts: covenant, fe9, ff8, ffx, etc
too many games to list man
I've always loved the Dragon Warrior series music and this is probably my favorite song from it. (https://youtu.be/OtHEeBaEaak)
Honestly, anything (https://www.youtube.com/watch?v=ZqYYOi3WO-M) from (https://www.youtube.com/watch?v=14U64jWO85s) the (https://www.youtube.com/watch?v=9k0rVqaA_2c) Etrian (https://www.youtube.com/watch?v=LPvBxglPNRI) Odyssey (https://www.youtube.com/watch?v=eMwBSGv-OrM) series (https://www.youtube.com/watch?v=y-f3unDc848). Yuzo Koshiro's amazing! Don't even get me started on the super arranges for EO3 & EO4--!
I also really enjoy the following games' soundtracks: Undertale, Kirby's Epic Yarn, Kid Icarus: Uprising, Tower of Heaven, Professor Layton series, Ace Attorney series and Pokemon RSE.
And then particular tracks I like... LoZ's Midna's Lament, Luminous Arc 2's Rosetta Rosso, Ace Attorney Investigation's Confess the Truth 2008, Chrono Trigger's 600AD Forest, Chapter 6 from Kid Icarus: Uprising (& anything Dark Pit related tbh or Aurum-related (hello again Mr Koshiro)) and even more I can't think of.
I just love video game music ):
Resident Evil 2's safe room theme. It gives you that feeling of saftey even though you're only safe for now. You know it's hell out there but in here, nothing can get you.
The LOZ Oracle games have some of the best music ever produced on the GB/GBC ever and is pretty much goes unapproved yes in terms of how well it is composed from an 8 bit stand point. It's pretty much under appreciated as a whole.
I'm not trying to get Mario busted or anything, but isn't can-can a copyrighted song? Or at least owned by someone?
It is from an opera so it's public domain basically