My ubuntu 11.04 was corrupted while run my python code?

I have developed the code in python2.6 for display the videos by using libavg. It was run successfully in ubuntu10.04. Later i decide that me want to execute that code in ubuntu 11.04. So that i was install ubuntu 11.04. Then only i found that 11.04 has python 2.7 instead of python 2.6.
Then i was installed libraries in ubuntu 11.04 which are needed to install libavg 6.0 packages and then i was installed libavg 6.0 . It was successfully installed in /usr/local/lib/python 2.7/dest-packages/libavg. Then i was paste my python files /code in opt/video. After while run my code it throws error as ERROR: ld.so: object '/usr/lib/libstdc++.so.6' from LD_PRELOAD cannot be preloaded: ignored.
Then i was checked whether it was installed or not by this command:ls /usr/lib | grep libstdc++. But it is available in lib folder. Then i decide restart the system and try to run once again. After restart the system boot and move to login page. after i was loged in, There is no menus are available in desktop. i was confused and try to open terminal through shorcut keys. but it also fails. Finally, i was restart my system again and again. but no use. Menus are not visible and ideally, the system shows empty desktop.
Why my ubuntu 11.04 was corrupted? what to do...