The ships in the movie where new creations just for the movie and except for using the same names and classes have nothing to do with Wing Commander...as did the entire movie...like the Final Fantasy Movie had nothing to do with any Final Fantasy part.
Still to solve some confusion here a small discription and pics how the ships looked ingame (the original games not Saga ^_^ )
Confederation:
The carrier is what should have been the "Tiger's Claw" a Bengal-class Strike Carrier.
This ship was your carrier in WC 1.

The fighters with that freaking big gun where Rapier-class medium fighters also from WC 1.

The Bombers where Broadswords from WC 2.

The ship Admiral Tolwyn is on is the "TCS Concordia" a Confederation-class dreadnought and your base of operations in WC 2.

Kilrathi
The fighter of the Kilrathi is called a Dralthi and the only ship in the movie that looked like something from the games.
You can meet a Dralthi from WC1-5

Destroyer...don't know what kind of class this ships should be.
Big Capship that dosn't have a navigation computer and gets sucked into a black hole is called a Snakier Class and is a heavy carrier.

If you want to know how other WC ships looked like here are two pages with some informations about the different ships.
http://www.wcnews.com/ships/http://tactics.solsector.net/joans.htmIf you would ask about my opinion about the movie I would say:
"That movie has never existed" -modified quote of the movie ^_^