OK. I guess I have no choice but to further display my Mac ignorance. I've been using a PC forever, but this is my first time with a Mac. Under my log-in, when I go to Finder/Applications/Utilities I get only three items: Migration Assistant.app; Remote in ... c OS X.app, and Terminal.app.
When I log-in under the previous owner's name and go to Finder/jan/Caches/Desktop I get Abstract.dpimageCache; Desktop Pictures.dpimageCache, Nature.dpimageCache, and Dolid Colors.dpimage.cache
When I go to Finder/Utilities (under her log-in) I get Migration Assistant, Remote Install Mac OS X, and Terminal
In the lefthand column two items are above the line: Network and Macintosh HD. Goiong to Network, I get Library and Servers. Clicking on Library I get the message "The alias library could not be opened because the original item cannot be found." Clicking "Delete Alias" I get: "The item 'Library' will be deleted inmmeidately. Are you sure you want to contine?" Saying OK, the response is "The operation cannot be completed because you do not have sufficient privileges for 'Library.'"
The previous owner and her late husband were pretty much computer illiterate so I have no idea what they did/did not do. This pretty much leads me back to my original conclusion that I may be better off just erasing the disk and starting over. That is, if I can find "disk utility."