"Recessive genes" is an incorrect way of looking at it.  A
"gene" is a
unit of inheritance, a stretch of DNA that codes for a protein or RNA,
that does a certain job.  An "allele" is the form that the gene can
take, or how well it can do the job.  Think of it using a bad analogy:
"gene" is like dessert, "allele" is like pie or cake. 
After dinner,
you need your dessert, but some people have pie, others have cake.

Since we (as mammals) have two copies of every chromosome - one from
mum and one from pop - we have two alleles for each gene.  If both
alleles are bad (mutated), you can sometimes see a defect (phenotype) -
e.g., albinism.  If both alleles are good, there is no problem.  The
trick is, what if one allele is mutated?  If the other allele can cover
the work-load, then the mutated allele is "recessive."  It's recessive
because one copy of the mutation is insufficient to create the
phenotype.  If the one mutated copy is sufficient to create the
phenotype, even if the other allele is normal, hen the allele is
dominant.

In the case of albinism, there are a few ways to become albino.  Say
you need two genes to make pigment for skin and hair.  A, and B.  Say
that alleles a and b are all recessive mutations of A and B.  A person
who is Aa Bb is fine (since a and b are recessive to A and B).  A
person who is AA bb is albino.  A person who is aa BB is also albino.
Now, if those latter two have kids, their kids will be Aa Bb, which is
fine.  So two recessive mutations can "complement" each other.
Hope that helps.
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