Geeze...!
Stick with Alison and Tinwhistler's picks.

The rest just seem to be naming every Celtic tune they can think of...

Not a very helpfull bunch of blowhards are they?

I assume that you wish to play in a session before you learn 250 new tunes, so try these:
Lannigan's ball,
Boys from the blue hill,
The Butterfly,
King of the fairies,
Sheebeg and Sheemore,
Fanny Power,
The Road to Lisdoonvarna,
The Ballydesmond Polka,
[don't worry about the other three that are often incorrectly referred to as "the Bally Desmond Polkas"(plural)]
Rocky Road to Dublin,
Over the Waterfall,[actually an American tune, but very common.]
The Parting Glass,
Banish Misfortune,
The Star of County Down,
The Lark in The Morning,
Oh The Brithes Full of Stitches,
Bridget O'Malley,
Bonnie Kellswater,
Kelly the Boy from Kilane
The Minstrel Boy,
Sheebeg and Sheemore,
Rosin The Beau,
The Black Velvet Band,
Planxty Irwin,

I think that every one will agree that if you learn this list you will find that most of the musicians at any session will know them, and will be happy to play them with you. [And they are not too difficult to learn.] The other tunes previously list ARE also very popular and would make great additions to your repetoire, eventually. I hope that this is helpfull... Dan