I guess I was not clear on my question.  The situation is only 3 physical drives in a machine configured with Raid 5 would there be any benifical affects of...

Dropping and recreating the indexes start with the smallest table and work up to the largest.  Creating additional space as you go.

One question, how big are the table after the deletes?  With archiving that many rows, I imagine that your tables are very large.  Your reindex could take hours so plan...