There are a few options. The first is consider going with a sealed crawl after the space is dried out.
The second and less costly option is to have the ducts tested and air sealed followed up by having them insulated to R8 which meets the state's new Energy & Residential Code. As for the bubble wrap, I hear it is good as a packing material.
For more information:
Read "How do you seal leaky ductwork?" a Q&A answered by David Edwards.
Also, read this blog post by Sean Lintow.