I can remember the very first time I heard the word foyer (pronounced foi-yay). We had moved to a new town in Louisiana, and this house was much larger than our old house. It had this beautiful entryway with stone flooring (I remember there seemed to be so much texture in that house), and I asked my mom what that room was called. She replied, "It's a foyer (foi-yer, as we said it there, and I still prefer that pronunciation even though it may not be correct)." At the time I could not understand why you would need a room that you only used for greeting guests, coming, and going.
But ever since I've been old enough to understand their practicality and how beautiful they can be, I've been a little obsessed with them. So I looked up the definition to make sure I was using the word correctly, since there are so many things we call the entryway of our houses.
A foyer is 1. an entrance hall or 2. a lobby or anteroom, as of a theatre or hotel.
An entry is a means or place by which to enter.
And a hallway is 1. a corridor in a building or 2. an entrance hall.
(All definitions from here)
Basically, all these things are interchangeable, and you can use whatever word makes you happy. I'm going with foyer.