It's been over a week now, and my wife is settling in to her new Debian system with no further problems. There were a few extras I needed to install when I first brought Debian up, and a few more I've needed during the last week.

Installed from the repository:

icedove - Debian's rebranding of Thunderbird, which my wife uses for email. The Debian KDE install does not include this by default.
msttcorefonts - the Microsoft TrueType core fonts; needed to make some web pages and some documents render correctly. These are in the Debian "Lenny" contrib repository, which is not enabled by default; I had to edit /etc/apt/sources.list to add it.
java - She needs this to visit some web pages. I was surprised to find the Sun Java Run-time Environment in the repository.
gftp - Our customary FTP program, for maintaining web sites.
beagle - She really likes this search engine for her desktop documents.
bum - The Boot-Up Manager, which I use to configure the system.
ssh and rsync - Her computer needs these in order for me to back up her hard drive remotely. (I was surprised that ssh is not installed by default.)

Some programs need to be downloaded and installed manually, not from the repository:

Acrobat Reader 9 - This is "non-free" software and thus not in the Debian repository; since she uses PDFs a lot, and the open-source PDF readers have problems with some documents, I installed this from the Adobe site.
hplip 3.9.12 - The older version in the repository does not include the drivers for her new HP multifunction printer, so I downloaded the latest version directly from HP.

I'll probably be installing GIMP for graphics editing -- from the Debian repository -- in the near future.

Worthy of note is one program I did not install: her old copy of Microsoft Word. She's been using this under CrossOver Linux, as a matter of habit, for all of her writing. On the new system I have added a shortcut for OpenOffice Writer instead. I've installed the MS fonts, and have OO Writer configured to save in .doc format by default, since she so often has to send documents to other people. If it becomes an issue, I can reinstall CrossOver and Word, but as of now, she's happy. (She said some of the changes have taken some getting used to, but it's mostly that accustomed functions appear in different places.)