How long does a game with most of the expansions usually take you guys? and what makes it take longer or go faster?

By "most of the expansions", you mean one?

The A Storm of Swords expansion usually takes between 1-3 hours if you use the companion map (on the lower end of that most of the time). I've never used any of the options with the base game.

Playing the normal game with A Clash of Kings Usually takes a little longer, if I'm remembering correctly. It's been a long time since I played anything other than A Storm of Swords.

My group tends to have games on the original map (not Storm of Swords) go from 2.5 hours (on a really good day) to well over 4 hours, especially when mixing in material from the expansions. Somewhere in that time frame would be our average.

My group can usually get a game done in 1.5 hrs, but we tend to know each other really well and can anticpate the moves of each other.