Most scanners you can buy now are pretty much plug-n-play. If you are running a recent version of Windows, it is likely that the system will recognize everything, and you may not even need to install a separate program to run it.
Generally speaking, the scanner will recognize what kind of picture it is looking at, and give you various options based on what you want to do with the scan (email, print, whatever). For "backup" purposes, I suggest you scan them as "big" as possible. It might take a little longer, but then you can do whatever you need in the future. If you scan only for email or web for example, you won't be able to make big prints of them later. CDs and DVDs are cheap storage if you have a burner.
It is really not taht difficult. Talk to the most knowledgable staffer you can find at Best Buy or whatever and tell them what you want to do.
You did not answer if the photos were slides or prints. One caveat - slide scanners make beautiful scans that are often very big files (35 - 75 MB). They also cost more than flat beds.
Andrew