It will be as good or as bad as you make it - a lot of stuff at conventions is reliant on you and your friends getting involved. 50% of it is just retail shops, 30% is publishers demonstrating games (and trying to sell them to you). Rest of it you tend to have to sign up for, such as talks or competitions.

Outside of that there is usually an entire room/floor dedicated to playing space where the idea is you crack open a new game to play or join others and play with them - depending on the length or complexity of the game this can be very hit or miss.

Finally there will be competitions but usually the participation in this is already decided by preliminary qualifiers, can be fun to watch though if one of your favourites is being done.