django - inlineformset_factory with more than one ForeignKey

Im trying to do a formset with the following models (boost is the primary):

class boost(models.Model):
   creator = models.ForeignKey(userInfo)
   game  = models.ForeignKey(gameInfo)
   name  = models.CharField(max_length=200)
   desc  = models.CharField(max_length=500)
   rules = models.CharField(max_length=500)
   subscribe = models.IntegerField(default=0)

class userInfo(models.Model):
   pic_url= models.URLField(default=0, blank=True)
   auth   = models.ForeignKey(User, unique=True)
   birth  = models.DateTimeField(default=0, blank=True)
   country= models.IntegerField(default=0, blank=True)

class gameInfo(models.Model):
   psn_id = models.CharField(max_length=100)
   name   = models.CharField(max_length=200)
   publisher = models.CharField(max_length=200, default=0)
   developer = models.CharField(max_length=200, default=0)
   release_date = models.DateTimeField(blank=True, null=True)

I want to display a form to add a Boost item, trying to do in this way :

   TrophyFormSet = inlineformset_factory(db.gameInfo, db.boost, extra=1)
   formset = TrophyFormSet()

Here is my questions :

1 - When renderized, the combo box for "Creator" show a list of "db.userInfo" (literally) ! I want this to display db.userInfo.auth.username that are already in the database... how to do this ?

2 - In this way, where is my "db.gameInfo" to choose ?

thank you ! =D

======

czarchaic answered my question very well ! Bu now i need just a little question:

When i use the modelform to create a form for the boost_trophy model :

class boost_trophy(models.Model):
   boost  = models.ForeignKey(boost)
   trophy = models.ForeignKey(gameTrophyInfo)
   # 0 - Obtiveis
   # 1 - Requisitos minimos
   type   = models.IntegerField(default=0)

class gameTrophyInfo(models.Model):
   game = models.ForeignKey(gameInfo)
   name = models.CharField(max_length=500)
   desc = models.CharField(max_length=500)
   type = models.CharField(max_length=20)

its work nice , but i want to the form to show in the "game" box only a realy small set of itens, only the : gameTrophyInfo(game__name="Game_A") results. How can i do this ?

If I understand you correctly:

To change what is displayed set the model's __unicode__ function

class userInfo(models.Model):
  #model fields

  def __unicode__(self):
    return self.auth.username