Users Unable to Access Software Installed by Administrator

Just got my sister a Inspiron 6400/E1505 from Dell Outlet as a Scratch and Dent product.  Windows XP Media Center is the operating system.  Love my sister to pieces, but she's not the most savvy computer user so we agreed that I would be the "Administrator" for her laptop and that she would not have privleges to install software, etc.  She bought some software (Quickbooks Pro 2007 and Calendar Creator), and asked me to install it for her.  No problem.  I installed both products under my name and launched them both to make sure they were working.

 

To get the feel for the new computer my sister was here yesterday using it so I would be available if she ran into a problem.  She of course logged in under her own name.  Neither program would launch when she was the User.  Quickbooks would act like it was going to launch but then would just stall and exit.  It didn't even show up in the Task Panel.  I logged in under my name (and I'm an Administrator), and lo and behold both programs launched with no problem.

 

I had to make her an administrator on the computer to enable her using this software.  Once I made that change both programs launched for her.  The problem is, when the computer asks her what to do (as an Administrator), she is not savvy enough to necessarily give the right answer.  What is the deal here?  How do you make programs available to all Users whether they have Administrator privleges or not?  I've never had to use these particular functions before as on my own computer I am the only user and an Administrator.  Help!