That sounds like a real blast.. I take the liberty to be the first to post some proposals.
As the 70s and early 80s were the golden era of Disco there is plenty to choose from but here are some of my favourites:
Bee Gees - Stayin Alive
Olivia Newton & John Travolta - The one that I love
Boney M - Daddy Cool
Weather Girls - It's Raining Men
Abba - Dancing Queen
Boney M - Rasputin
Eruption - One Way Ticket
Bonnie Tyler - Holding Out For A Hero
Whitney Houston - I Wanna Dance With Somebody
Laura Branigan - Gloria
The Jacksons - Blame It On the Boogie
Abba - Waterloo
The Pointer Sisters - I'm So Excited
The Trammps - Disco Inferno
Earth, Wind & Fire - September
The Jackson 5 - I Want You Back
Santa Esmeralda - Don't Let Me Be Misunderstood
Cindy Lauper - Girl want to have fun
Sabrina - Boys
As for the 90s, a lot has changed and music "evolved".
I don't know if you still can call it DISCO but here are some iconic dance songs from the 90s which should entertain us all I hope
La Bouche - Be My Lover
Venga Boys - Boom Boom Boom Boom
Backstreet Boys- Backstreets Back
Ricky Martin - Livin La Vida Loca
Culture Club - Charma Chameleon
2 Unlimited - No Limit
Lou Bega - Mambo No 5
and of course
Rick Astley - Never Gonna Give You Up