Constant Crashes

I really am frustrated. I had a mid-2010 MacBook Pro, and I got Final Cut Pro X, and it kept kernel panicking. I thought, "Well, okay, it's not a powerful machine, maybe if I bought a more powerful iMac, it wouldn't crash." I guess I was wrong. I have a Mid-2011 21.5" iMac (2.7 Ghz i5, 12 GB RAM, OSX 10.8.2), and every few months, Final Cut Pro X starts to crash for no reason. I usually reinstall it, and it fixes the problem, but this time, reinstalling hasn't fixed the problem. Deleting the preferences also hasn't fixed the problem, and I have no idea what's wrong with it. It'll open fine and run fine, but when I try to drag a clip longer than 30 seconds into the timeline, it just crashes. It's been super frustrating, and if anyone knows what this error code means, or can tell me how to fix the problem, please tell me what the problem is:

I run a 2007 MBP with not much trouble at all.

What source is the video that you're importing from?
How much RAM?
GPU?
What is your hard drive configuration?
Where are Events and Projects stored?
Have your run Disk Utility or Disk Warrior?

Where are you storing your media? Locally or on an external drive?

The footage is from my camera (it's a Sony Handicam)
12 GB RAM
AMD Radeon 6770 M - 512 MB VRAM
1 TB Harddrive (not partitioned) and a 2 TB External Harddrive
The footage is on the internal drive
I repaired disk permissions in Disk Utility.

Put all Events and Projects on the secondary drive, NOT on the system drive. That could cause issues due to the limited bandwidth. Get Disk Warrior and repair the directories of all connected drives.

How do I move the events to the external drive and make Final Cut look there for them?

Here's the section of the user manual with all of the info you need.
help.apple.com/finalcutpro/mac/10.0.5/#ver4e2e1bd

There are two folders, "Final Cut Events" and "Final Cut Projects". On the system drive, they must be in the Movies folder. That's so each user who logs in only sees their own work. But for all other drives, they simply live on the root level. They can be on any attached drive. You can have stuff on all your drives if you want.

In your Movies folder, simply copy those two folders to the external drive. Then delete them from the system drive. Do not keep both copies, FCP X will have issues with duplicated database ID numbers.

Great advice from Ben about moving your movie files off the system drive, but I'm not sure it will affect the crashing. Here is what I would try (to help troubleshoot the problem). With each step, let us know whether the problem has been fixed.

1. Create a new user account and log in with it (so it's fresh). If this works, most likely the problem has something to do with something else installed on your system that is conflicting with it.

2. Use compressor to convert your original media to ProRes 422 and bring it into FCP that way. If this works, perhaps the file from your Sony camera is either corrupted, or the codec that it's using on your system is. As an aside, is it footage from your camera longer than 30 seconds that causes it to crash, or is it any footage?

3. Make sure all your system software is updated. Worst case, reinstall the OS. I know it's a pain, but I try and keep my edit system very clean, so I do a reinstall once a year. BTW, what system version are you running?

Let us know if you have any luck!

For what it's worth...
The new account is definitely worth a try to eliminate OSX issues.
The Sony handicam shouldn't be an issue, although we don't know what format or codec the files are. I have a Sony Handicam that shoots 1080 60p in AVCHD and the footage imports from camera perfectly.
Re-installing the OS and/or FCPX is something I would not do. There is certainly a way to fix what the issue is and in 10 years of using MACs and 9 years FCP, I have never had to reinstall either. It's worth the effort to look for what is causing the problem in my opinion.

I have seen on a couple of my students MBPs where moving stuff from OS drive to a secondary media drive helps with crashes an other problems. I like to start with the simple solutions first.

I tried moving the events and projects to an external drive, still crashing. Also restored to a backup from before the crashes started, but it just crashed again.
Also tried a new account, still crashing.
Also tried editing a different project, still crashing.
I'm going to try to remove the event that started the problems and see what happens.

EDIT: Not only did that not help the crashing, it made it worse. I tried editing something else and my entire screen went black. Then the computer displayed a message in multiple languages saying "Your computer restarted because of a problem. Please press a key or wait a few seconds to continue starting up."
Uhh, what's going on? I think the problem is bigger than just an event...

My guess is a hardware problem. Bad RAM, bad video card, or even the logic board. I would take it to your local Apple store and have them run some tests.

Yep, that message is a serious hardware failure. Nothing to do with FCP X at all. Get it to an Apple store or authorized Apple service center ASAP.

Hi there, I agree that last message seems to indicate a hardware problem not related to fcpx. But I would still suggest one other fix I haven't seen mentioned yet in this thread, and I'm trying to post it in several places so that people know more about this particular and annoying bug causing crashes and playback problems. I for one have had many issues with playback when using any color profile for my monitor other than the built-in standard one (I am on an imac, so that would be the imac basic profile). If you have calibrated personally your monitor, try quitting fcpx, going to system preferences, monitor, and setting the color profile to the default one.
This has helped me several times when experiencing problems with playback (black monitor) or simply having the app crash when trying to play ANY clip...
Maybe you have another problem, but I would definitely try this.
Also, the last message you got from the computer might indicate a RAM problem. I saw you have 12 GB of RAM: did you install any supplementary memory yourself? If so, are you sure you picked up an absolutely compatible module with your mac model? This can be tricky as every year macs get different RAM packed into them. I would recomend searching for compatibility with your model on the CRUCIAL site, they have a good way of helping you see if your memory is compatible.
Anyway, hope any of this helps.
Good luck and let us know if you find a solution!