the image from above is an image that samsung uses to notify the user of an absence of a readable boot file. Your phone is not bricked, but rather soft bricked. It is in a state that cannot load the image from rom. You just need to re-flash the phone.
Uhh, I may have been mistaken on doing it with the phone on.
Remove battery, put back in, leave off, unplugged.
Press keys in order. Hold power button until menu appears.
The combination that people are telling you to press ( Send Key+End Key+Lock Button ) is the sequence used to hard reset your phone. This won't have any effect on your phone, as it can't wipe the system and reload from rom, because this is where the problem is.
And the volume up or volume down is incorrect. That is only for the i8000 Omnia 2, Not the i920 Omnia 2 phone.
Just remove the battery, replace the battery, setup your loader with the correct rom file and click detect.
Reconnect your phone via USB and your phone should flash just fine.
If the phone is not recognized then there is a usb driver/connection problem that needs to be dealt with. First restart your computer and re-set it back up. then plug the usb cable back in. You may need to try different ports (front vs. back) on your computer as well.
again, your not bricked, just challenged to flash another rom.