Rayman 1 - 5 : Peaceful Peaks 4 : Venomous Mr. Skops 3 : Mr. Dark's Dare 2 : Harmony 1 : The Stalactites' Teardrops
Rayman 2 The Great Escape - 5 : The Sanctuary of Water and Ice 4 : The Grolgoth 3 : The Teensie Circle 2 : The Woods of Light 1 : The Four Masks
Rayman M (I'm just going to put the characters themes for the races as their variations aren't that different and I don't remember them well enough) - 5 : Razorbeard 4 : Haunted Yard 3 : Rise and Shrine 2 : Henchman 800 1 : Rayman
Rayman 3 Hoodlum Havoc - 5 : The Hoodoo 4 : Factory Mayhem ~Perilous Pathways~ 3 : Reflux ~Ascended Knaaren Warrior~ 2 : The Summit Beyond the Clouds 1 : Reflux ~The Knaaren Warrior~
Rayman Ravings Rabbids (GBA) - 5 : The Organic Caves 4 : The Village ~Dawn~ 3 : Crush Him ! 2 : The Rabbids' Lair 1 : Trees and Kalimbas
Rayman Origins - 5 : (Gourmand Land) Dashing Thru the Fire 4 : (Gourmand Land) Breaking the Ice 3 : (Jibberish Jungle) Breaking the Force Field 2 : (Land of the Livid Dead) Nowhere to Run 1 : (Land of the Livid Dead) Chasing a Dream
Rayman Legends - 5 : Hades' Hand ~The Platform~ 4 : Teensies on Trouble 3 : The Tower of Babel ~Rising~ 2 : A Madman's Creation 1 : Hades' Hand
I gotta admit, I'm not a big fan of the Origins and Legends soundtracks.
Since I already made a top 5 here before (which I greatly simplified in the quote so this message isn't as long as a whole page), I'm gonna do a bold move and go against this topic's rules... by remaking it and extending to TEN tracks for most games I already listed! AND with my fav fangames included!
Rayman 1:
10. Harmony
9. Moskito's Rage
8. Blazing Brass
7. First Steps
6. Peaceful Peaks
5. Mr. Stone ~King of the Mountain~
4. The Stalactites' Teardrops
3. Betilla the Fairy
2. Venomous Mr. Skops
1. Mr. Dark's Dare
("Woah, like, dude doezn't has same opinionz anymoar!
")
Rayman (Jaguar):
5. Betilla
4. The Magician's Challenge
3. Mr Dark's Showdown
2. Crystal Palace
1. Harmony
Rayman Advance :
5. Mr. Dark's Dare
4. Space Mama's Finale
3. Peaceful Peaks
2. Painted Pentathlon
1. Entering the Cavern
(Not gonna do Rayman Ultimate becuz doing a top 5 in a selection of 10 tracks isn't particularly meaningful
Same goes for other games like Hoodlums' Revenge...)
Rayman 2 The Great Escape/Revolution:
10. The Cave of Bad Dreams
9. The Whale Bay ~Bubble Trail~
8. The Hall of Doors
7. The Grolgoth
6. The Teensie Circle
5. The Sanctuary of Water and Ice
4. Polokus ~Spirit of the World~
3. Ly the Fairy (
Yellow Alien Chick do be magical

)
2. The Woods of Light
1. The Four Masks
(That one was so difficult to decide, every piece of this OST is just so wonderful that I just hate picking favorites!
)
Rayman 2 The Great Escape (N64):
5. The Grolgoth
4. Tomb of the Ancients
3. The Flying Barrel
2. The Precipice
1. Main Theme ~The Great Escape~
(Ooh... I'll admit, I really don't like this version... I always struggle to pick pieces which I actually like in this one, a few are an interesting take, but everything else is so... dull...
)
Rayman (GBC)/Rayman 2 Forever:
5. Rainy Forest
4. Ancient Forest
3. Spellbound Forest
2. Credits
1. Airy Tunes
Rayman (PDAs):
5. Ancient Forest
4. Spellbound Forest
3. Title Screen
2. Rainy Forest
1. Airy Tunes
Rayman M/Arena:
10. Razorwife's Theme
9. Globox's Theme (OMGEE GUYYYZ! ITS TEH GLOBOX MOMENT!!

)
8. Haunted Yard
7. Henchman 1000's Theme
6. Gemstone Temple
5. Coconut Island
4. Rise and Shrine
3. Henchman 800's Theme
2. Razorbeard's Theme
1. Rayman's Theme
(Yes, no Tily allowed!
)
Rayman 3 Hoodlum Havoc:
10. The Fairy Council
9. The Calm of the Lake
8. The Hoodboom
7. Clearleaf Forest
6. In the Fairy Hallways
5. The Hoodoo
4. The Great Hall
3. Leptys/Ascended Reflux (all the final themes in one because why not)
2. The Summit Beyond the Clouds
1. Reflux ~The Knaaren Warrior~
(11/10 Many plums tunes, would eat a black lum again!
but so hard to pick among so many favorites again!
)
Rayman 3 (GBA):
5. Vertigo Wastes
4. Heart of the Ancients
3. Den of Rocky
2. Shining Glade
1. Title Screen/Credits ~Rayman's Theme~
(Rayman 3, but it's actually Rayman 2 again because we couldn't make up our minds
)
Rayman Ravings Rabbids
5. The Dark Laboratory 3 ~Doom~
4. Taming the Wild West 6 ~The Giant Robot~
3. The Rabbid Graveyard 1+4
2. The Warthog Race 1
1. The Warthog Race 3 ~Dark Iron Bunnies (Instrumental)~ [I made Rock'n'Run, so can you blame me for this pick?

]
(Note: Bwahbwahbwahbwah!!
[Translator's note: Rabbids freaking SUCK!
])
Rayman Ravings Rabbids (GBA)
5. The Organic Caves
4. The Rabbids' Lair
3. Trees and Kalimbas
2. Crush Him!
1. The Toy King [why didn't I pick this one before?

]
Rayman Origins:
10. (Sea of Serendipity) The Abyss [wow, a serious ambient track in a UbiArt game!? WHAT SORCERY IS THIS!?

]
9. (Gourmand Land) Frozen Paradise
8. (Desert of Dijiridoos) Lost Beats
7. (Jibberish Jungle) The Darktoon Chase
6. (Mystical Pique) Scaling the Mountains
5. (Ticklish Temples) Poor Little Daisy!
4. (Moody Clouds) Destroy the Mechas!
3. (Land of the Livid Dead) Nowhere to Run
2. (Land of the Livid Dead) Chasing a Dream
1. (Bonus) The Final Showdown [why did we get dat stupid wannabe Magician instead of Mr Dark?

]
(7.8/10 Too much water chipmunk ukuleles, not enough plums, wouldn't listen again
Nah, seriously, it's actually very good!
)
Rayman Legends:
10. When the Wind Blows [a serious, actually enchanting moment in a UbiArt Rayman? IMPOSSIBLE, this must be a trick!

]
9. Teensies in Trouble
8. Laser Mayhem
7. The Tower of Babel
6. A Madman's Creation
5. Castle Rock ~Black Betty~
4. Hades' Hand
3. Mariachi Madness ~Eye of the Tiger~
2. Grannies' World Tour ~Chasing a Dream~
1. Dragon Slayer ~Mecapiston~
(I'll admit, I'm not a HUGE fan of the UbiArt soundtracks!... Oh, I do really like them actually [EXCEPT MINI
], it's just that I'm neither tall nor fat.
)
Rayman Mini:
1. Shady Contracts
(YES, just ONE, and it's just in honor of Mr Dark! This soundtrack just *EFF*ing SUCKS! People -rightfully- complain about Rayman GBC and Advance for having soundtracks that can be a pain to the ears, but this!? There's no platform limitation excuse you can make in favor of the ear-piercing cacophony that is... whatever THIS is! I'm sorry, Héral, but it's about darn time to change that "backpack" of yours! I gave it a genuine chance and really wanted to like this one, but my ears BEGGED to make it stop!
)
I'm not even going to do honorable mentions for the official games even if I would love to add them, or else I'll end up listing the e n t i r e soundtracks for the original trilogy 
(Yes, I'd even include this absolute banger from R3
)
So instead, I'll just take the time to say the Rayman by Rémi tracks are some of the greatest masterpieces ever made around Rayman's world and you should totally give them a listen!
Fangames:
Rayman The Dark Magician's Reign of Terror:
Note: please, listen to the high-quality stereo version of the soundtrack.
5. Lush Island
4. Savage Minion
3. Pascal
2. Dark Magician First Battle
1. Dark Magician Final Battle
Honorable mentions: Grim Chains (Dark Magician's Challenge/Flint Jail in Redemption/ReDesigner), Piranha Shoel (Mr Smushy Boss), Wire Walls, Techno Freeze, On The Sky, Living Plums, Alien Assault (U.F.O Boss), The Final Frontier, Alien Android, Angry Cacti (Mr Cactus Boss final version), Haunted Gardens, Fiery Fort, Freeing the Magician, Freezy Freezer, Cold Reception, Dark Storm, Eye of the Storm [long list, ain't it? This soundtrack is just that good!
]
Rayman Redemption/ReDesigner:
5. Child's Play
4. Darktoon's Mischief (OST version, which has an exclusive intro bit)
3. The Dark Chimera
2. Corrupted Protoon
1. Battle for the Great Protoon
Honorable mentions: Redemption, Jaguars in the Jungle, New Foe, Mountain Spring, Molten Depths, Bottom of the Toybox, Brain Games, Mr Dark's Domain, Flight of Dark Rayman, The End of the World, Dark Legacy.