not knowing exactly what details you wife puts for each apt or
how this is organized - I'm going to show you a SUPER easy way of doing
this.

Google Calendar.

I use this DAILY doing just what your wife does - setting appts.

You click on the day of the month, click the hour, input the name, click
Done.

You can access it from any computer (win or lin) and from home or work.

If you need more sophisticated features -- this might not work but -
check it out first.

Here is an example Windows app. These mimic the appointment book with a few
extra features.

betterwindowssoftware.com/Appointment-Book-Pro-Business-PIMS-and-Cale
ndars-commercial-113734.html

As is usual with W$ apps, these appointment book programs are VERY
EXPEN$IVE. Typically they cost about $295 or more. On top of the expensive
M$ software, you could expect to pay more for the software then the
hardware.

But I'm preaching to the choir here.

I would agree with Wade here, Google Calendar. If you need phone
support (Treo, Blackberry, etc...) then you're looking at a Windows
app, but they should come with that. However, Google Calendar is just
absolutely awesome, I can't use it with my Centro myself (running Mac
OS X on my primary computer, so use iCal). However, there is NO
REASON to PAY for expensive Windows software to do what Google
Calendar does anyway.

Korganizer can manage multiple people and tasks

That looks like it. I'll check it out.

http://kontact.kde.org/pics/shots/calendar.png

What about the calendar in Evolution?......