iPad 2 crashes at usage
Have you tried restoring it? There could be something app or service running that you are not aware of, thats causing it.

I would try doing that.

Restore to new, and install a couple of app and test it for a day or two to see if it still crashes.

Before you do, take a full backup to your computer!

If that doesn't work, you probably need to have it looked at by a pro.