Scanning resolution for small images

[Phil]

I am scanning a number of old family photos to publish in a book. A lot of these photos require only a small portion of a 4x6 print - often an area only about 1"x2". What resolution should use to scan that small area so that I can use it in a 2- or 4-picture/page layout? I don't intend to use these scans for full bleed.

Thanks for getting back to me right away. I am working on my first book and have a deadline only a month away.