Autodesk only officially supports AutoCAD 2010 and newer on Windows Vista and Windows 7. Older versions were not designed for the Vista UAC(User Account Controls) and security built into Vista and Windows 7. AutoCAD 2002 wasn't even designed for Windows XP.
Then there's the whole problem with 64 bit operating systems and how 32 bit programs have to be designed slightly differently for 64 bit operating systems.
While the newer versions of AcroPlot are compatible with Windows 7 it doesn't mean that we are going to be able to drive older versions of AutoCAD externally on Windows 7. Getting an older version of AutoCAD to run on Windows 7 is one thing. Getting a program to be able to drive an older version of AutoCAD is a whole different problem.
AcroPlot is officially supported on Windows 7 but only with versions of AutoCAD (2010 and newer) that are also supported on Windows 7.
For older versions of AutoCAD on Windows 7 you will likely have to set both AutoCAD and AcroPlot to Run As Administrator because the older version of AutoCAD likely needs elevated rights to run. You will also likely have to set AutoCAD to run in Windows XP, SP3 emulation mode.
Now you may ask why AcroPlot would have to be set to Run As Administrator when it is Windows 7 compatible and you want to use a version of AutoCAD before 2010. The reason is because of the Windows UAC and a program cannot start another program that requires higher privileges. So if AcroPlot is running as a normal user and it tries to start AutoCAD 2002 which you have set to Run As Administrator then it will fail. At this point you can either run AcroPlot from inside of an already opened AutoCAD or you will have to set AcroPlot to Run As Administrator also.
Here is a good write up of how to get older versions of AutoCAD to run on Windows 7.
http://www.longbowsoftware.com/Tips_and_Tricks.php