I'm a photographer myself and no it's not a good idea to have both CS versions installed at the same time. If she is using CS5 then she has no more need for CS2. If she wishes to use CS2 for whatever reason, then I suggest she places it on a new computer, or you run a dual boot O/S such as win xp/win7. That way they don't conflict with each other. I use CS5 myself and feel it is more than sufficient to get the job done. As the previous poster stated, it's also an issue with the other program as well. Sometimes you just can't have the best of both worlds.