I want to remove items from copy of form before .serialize()... but how?

I want to remove items from copy of form before .serialize()... but how?

OK, this sounds strange, but before a form gets submitted, I want to grab all of the data being submitted, and serialize to insert in a separate variable that's also part of a process that's separate from the form submission itself.  The problem is, I only want to grab and serialize certain form elements (specifically, those that aren't "type='hidden'").  What's the best way to grab the form, duplicate the object temporarily, and remove certain elements from it, so I can then run .serialize() on it before attaching the results to my other variable.

Many thanks! 

Cheers,
Lelando