Backup questions

I have 2 questions.

1. What is the best way to back up a production box running Postgres
nightly?

2.  I thought the best way was to create a script that would use pg_dump
to 
create a dump every night and then use restore if I need to.  I did this
but
I am having a problem.  Apparently there were a few Primary key Big
Serial 
fields that had the name changed on them after they were created.  The 
backup works fine but during the restore it fails because it thinks
a relation is missing.  Before restoring the database with the changed
fields works fine, I just cannot get it to restore.  Is there something
in the background that Postgres is hanging on to after I renamed the
fields that is preventing me from restoring?  How can I work around
this?

Thank you
Jason Tesser
Software Development
NMI 715-324-6900 x5273