Try uninstalling the application and then reinstalling it, but first . . . make sure that you are running the correct version of Blender. The site offers up several versions depending on what operating system you are running.
Next, make sure that you are selecting most of the installation options suggested by their installer. For some reason, their installation suggestions are not really suggestions. Blender seems really picky about this stuff.
Before reinstalling the program disable your virus and spyware protection until you have it fully reinstalled.
The program kept shutting down every time I used the right mouse button until I uninstalled and reinstalled and this time disabled my virus protection and spyware detection and selected all of the suggested installation options.
If that does not work for you then try the Blender forum sites for more help.
[Edit] I spoke too soon. Even after doing all of the above the program would crash whenever I tried selecting new items to move with my RMB. I got on the forums and asked for help. Nothing suggested worked for me and I very nearly quit using the package. Actually I did quite. But when I retried Blender's freeware competitors I was so dissapointed in the results, in the feel of those lesser programs, that I finally reinstalled Blender and went back to the forums and tried one last time. Success!
It turned out that Blender did not like my graphics card one bit and I actually needed to turn off the hardware acceleration feature. I did this and now--so far anyway--Blender works perfectly for me.
Some users find that they need to turn their setting from 32 to 16 bits while others have no problem whatsoever utilizing Blender on their current graphics card settings. It's freeware. You download it, give it a try, go to the forums if it behaves in an uncivilized manner, and then decide if you can live with the proposed fix.
Since it takes all of thirty seconds for me to turn on or off hardware acceleration I find that I can live with my particular fix. Best of luck to you.
Eternal student in search of knowledge. But will settle for the occasional epiphany.
