Assuming your crash is being caused by one of these evil "undeliverable mail" notifications, I have a solution that is similar to earlier offerings, but there are a few additional requirements. Here is the recipe:
1) In Settings, turn on Airplane Mode
2) In Settings > Mail, Contacts, Cal
Select "Preview" and set it to "None"
These two steps alone keep Mail from trying to prematurely read that nasty e-mail and crashing on you. You now can at least open Mail with confidence and scroll through your Inbox to find the culprit(s). According to the suggestions above, you can now go into Edit mode, select the offender(s) and delete them. Unfortunately, that didn't work for me, because as soon as I highlighted the first renegade e-mail for deletion, Mail accessed that bad boy (presumably to render the contents for me in the window to the right) and summarily crashed.
So here's the final important piece of the solution: instead of going into Edit mode, swipe your finger from left to right directly on the evil e-mail. This causes a red "Delete" button to show up right on that e-mail without highlighting it! So no crashola! Mash that "Delete" button and send that naughty nellie to the trash. If you want, you can chase it into the Trash folder and pull the same stunt there to be rid of it for good. But if you do, beware! Make sure that you also have a more recent e-mail in the trash with it so that when you enter that folder, our nemesis doesn't get selected and crash you right back to where you started!
Repeat the process for each of these meanies. Close Mail. Open it again. Confirm the evil-doers have not returned. Close Mail.
Go back to Settings and undo what you did in the first two steps.
Open Mail. Smile.