Every time I try to join the server, MC has a panic attack and crashes. I think its because I clicked on 'Force Manipulator' the my game crashed.

What is the error that you are getting?

I don't get any error, My client just closes.

Have you tried deleting your client and reinstalling it?
You can also try changing to a older version and then back to the current recommended one.

Other than that you may be having a Java issue if you recently installed a Java update since java sometimes has issues with updates.
You would need to Uninstall all versions of Java. Delete the folders that it installed to, reboot (import step), and install the newest version.

Still having issues?

Yep, uninstalled Java and Tekkit and still it crashes. Maybe you could change my location so I login at spawn.

It was the MFFS mod that was breaking your game.
I literally had to change the config so I could get in there and destroy it because the field was bugging out.
Force manipulation will be disabled until they fix it in an update, and I don't know how well the other features of the mod will work, but you should be able to log back in and play now.
Just be careful with mffs until we see a server-side fix.

Also, next time please add more details to your posts for help.
It's so that we can find your location and know exactly how you found a bug etc, and so we can
better help you when things like this happen.