Archiving old family photos

I've found several sets of very old family photos on both my father's and mother's side of the family.

I've been wondering the best way to archive them.

I've decided to:
1) Use jpg files for digitizing the old photos
2) Use Picasa for adding captions (I've been told that it has the added advantage of face recognition, so it may help to identify relatives in photos if you have them identified in one photo and want to figure out what other photos they are in)
3) Probably buy two external hard drives to store all our photos on: one for hear at the house and the other at a relatives house for an "off-site backup"
4) I will keep the old photos since that seems the safest way of preserving them

Here are some websites I've found helpful:

• National Archives - Don't throw away old photos after digitizing them
• Caring for your Family Archives (From the National Archives)
• National Archives Blog post on digital preservation "Four Easy Tips for Preserving Your Digital Photographs"
  
• The Best way to add captions to digital photos (this also names 4 good tools for photos)
• Archival File Formats for Digital Storage (recommends formats, media and more)
  
• A few methods to archive
• Wikipedia Article on Digital Preservation
• White Paper "Digital Imaging for Archival Preservation and Online Presentation: Best Practices" from Michigan State University

Do you have any questions or suggestions along these lines? Please comment!