Client (very rarely) freezes on loading screen

I joined an ARAM game this morning. The game was taking a while to load up, so I tabbed over to Firefox while I waited. After reading an article or two and the game still hadn't loaded, I began to suspect that something was wrong. I force quit league and restarted. Upon doing so, I got a bugsplat popup infoming me that League had crashed and gave me the following message in Firefox:

"Crash Report #132669560

A 3rd party application has cause the game to crash. Please deactivate or uninstall any 3rd party apps that modify the League of Legends executables, in order to prevent future crashes. "

There are no applications modifying League, so I can only guess that the message is referring to my using the task manager to force quit League from whatever weird state it had gotten itself into.

When I finished restarting League and rejoined my team, the game was already 13 minutes in with minions on the nexus towers. I apologized to my teammates for the delay and one of them stated that the same thing (league crash) had happened to several of them as well.

I'm not sure how to duplicate this as the crash is, fortunately, quite rare.

Furthermore, the client's help menu says I can submit logs in the following manner: "Once in the PVP.net preferences menu, you can select "Submit Logs to Riot" to send us this helpful information, along with your own descripting of the problem. " Maybe I'm blind, but I can't seem to find this option. (also, it should be "description" not "descripting")