An excellent list. However, there are a few errors that need to be ammended:
: This was first used by Winonas shiny Swellow, in Sky High Gym Battle.
: This one is arguable, but Lugia is said to use Aeroblast in The Power Of One. Its easily confused for Hyper Beam though, so you can take it either way.
: In Dittos Mysterious Mansion, Duplica commands her Ditto (transformed into Ashes Bulbasaur) to use Constrict. Bulbasaur isn't able to learn the move, but I think it should still be counted.
: Fly is considered to be very different from the games to the anime. In the games it is a 2 turn attack, but in the anime, it can be applied in any case in which a Pokemon flies above and then strikes the opponent. In this case, Pidgeotto would be the first to use it (in Ash Catches a Pokemon), but you have the attack down as Wing Attack, so ignore this one.
: A similar case to Constrict: It was used before in Hoenn by Nuzleaf, but Nuzleaf is unable to learn Grasswhistle as far as I know. I still think you should count it though.
: You got the Pokemon right, but the wrong episode: Gligar first used this in From Brags to Riches against his opponents Machamp.
: Not really an error, but the first episode Weezing used this in was The Evolution Solution. Just pointing that out.
: Missingno Master pointed this out, but a Gentlemans Raticate first used this (granted, Raticate cannot learn the move).
: This was first used by the Nidorino on the television in the first episode.
Ice Shard[/B]: Was first used by Mays Glaceon in Strategy with a Smile.
: Lock-On was not a move at the time Electric Soldier Porygon premiered, so that would make Brandons Regirock the first to distinguishably use this (in Battling the Enemy Within). Porygons seemed more like a feature it had rather than a move.
: On the episode title, you forgot the Attack in Spinarak Attack.
: Same case with Lock-On. I can see where you got the assumption of Squirtle using it first in Kanto from, but Rapid Spin was not a move at the time, making Chigusas Hitmontop from 2 Hits and a Miss the first to distinguishably use this.
: This was first used by an Armaldo in the Hoenn episode Where's Armaldo.
: Meowth first experimented this on Ash in Challenge of the Samurai.
: Not really important, but it is spelt wrong on the first page (as Strenght)
: There is no way that Pikachu used the most powerful Electric attack (at the time) in the first episode. The first time Pikachu officially used this was in Showdown at Dark City.
: The same case with the last one, except this time Pikachu first used it against Brocks Geodude in Showdown at Pewter City.
: This was apparantly used multiple times by Beedrill before Hoenn, but the first time it was commanded was by Jeanette Fisher in The Fourth Round Rumble.
Also, many people are calling the move Tangrowth used in DP134 Secret Power, seeing as how it puts the opponent to sleep. Bulbapedia says this too, but I'm unsure if it is Absorb or Secret Power. If anyone can confirm this for me, I will be very grateful!
I know there are likely more errors, but these are the ones I noticed.
Apart from these, this list is amazing. It's truly fantastic to finally have somebody dedicated enough to put this massive compilation of moves up for everyone to see. Only problem I see is that it will have to edited often! =D
EDIT: Thanks dman dustin. Must have had a brain fart forgetting Winonas Swellow!