You can probably find your answer in the following link: (http://www.pymolwiki.org/index.php/Ideas)

Alternatively, pi-pi or other weak interactions and their all quantitative details also can be calculated for your system through ORTEP-PLATON program. You may try that too.

Thank you very much.

hi, 

Discovery Visualizer is the best to find out the Pi-Pi interaction.  

Although not directly related to your requirement (DNA and Ligand), if you are interested in analyzing pi-pi interaction and interaction network within a protein, then iCAPS module of iRDP  (http://irdp.ncl.res.in) server might be useful.

With iCAPS (in silico comparative analysis of protein structures), one can compare at most 100 protein structures simultaneously with respect to differences in aromatic-aromatic residue interaction networks present among them.

Besides aromatic-aromatic interactions, one can also compare other structural features.

Thanks

We have developed a program called MolBridge (http://nucleix.mbu.iisc.ernet.in/molbridge/index.php)....U can try dis, where we give the area overlap also....

Thank you very much for the answer.