How Many Open Apps?

Should my users be having trouble if they leave all these open all day?:
-Illustrator 9
-Photoshop 6
-Quark XPress 4
-Adobe Type Manager Deluxe 4.6
-Outlook 2001 for Mac
These are G3s and G4s with OS8.5.1 through 9.2.2. Most have about 384MB RAM plus Virtual Memory turned on. They appear to crash quite a bit with varying errors. They also have Wacom graphics installed as well as the LaserWriter 8.6 extension.