So this is the first Gen Con for my hubby and I. I consider us big gamers, however in the Gen Con world I think we are more beginners.
We play and LOVE D&D 5E, I thought I saw something about a large D&D game that has like 50 players and you move from table to table? This sound familiar to anyone?

thanks for the help! 

That doesn’t sound familiar. Usually larger companies have several tables running the same adventure at the same time though.

Baldman Games runs D&D events and some of them you can run thru one and then goto the next which is the next in the series and keep progressing. Is that what you were referring too?

This sounds like the D&D Experience offered by Baldman Games (Example link: https://www.gencon.com/events/161815)

These are generally 4 four-hour sessions in their own area away from the rest of the gaming. You play the game with the same group throughout all adventures. 

Baldman games run multiple tables of D&D 5E and also run an experience events.. https://www.gencon.com/events/161815

The Experience events are around $150 per person so that can be expensive for some.

Most of the other events are showing sold out however I know from experience that if you show up about 20 mins early for the event with generic tickets they can usually find a table for you.  If you want to see if this is your cup of tea then try the shorter session https://www.gencon.com/events/160827 first then go from there. You can level from 1- 20 during the con. this is what my group is doing this year.

Have fun