Any PAL/NTSC(U)/NTSC(J) Wii can be bricked or semi-bricked if you play an out of region game disc on your Wii + it has a region update on it.
Below is a guide to follow when playing a Game Disc that has a firmware update on it.
NTSC(U) Game + NTSC(U) Wii = No chance of a region brick
PAL Game + PAL Wii = No chance of a region brick
NTSC(J) Game + NTSC(J) Wii = No chance of a region brick
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NTSC(U) Game + PAL/NTSC(J) Wii = Brick is possible if Wii is not updated with latest firmware + Wii Brick Blocker.
PAL Game + NTSC(U)/NTSC(J) Wii = Brick is possible if Wii is not updated with latest firmware + Wii Brick Blocker.
NTSC(J) Game + PAL/NTSC(U) Wii = Brick is possible if Wii is not updated with latest firmware + Wii Brick Blocker.
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The safest (100%) way to play your Wii without a possible region brick is to play game disc that are the same region as your Wii system. (If you use downloaded games make sure the Game Disc is the correct region and not patched from another region)
If you Region Patch a game disc or enable your region free option on your Modchip follow the below steps to protect yourself from a region brick...
1) Update your Wii to the latest firmware version available from Nintendo. (As of now 3.1 is the latest) To find out what version you are currently on do the below...
Click on the Wii symbol in the bottom left hand corner. Go to Wii settings. The firmware version is in the top right hand corner. (3.1U = USA/3.1E = Europe/3.1J = Japan)
2) There is a new program out called Wii Brick Blocker. You can run this on the Game ISO to patch it. It changes a string on the Game Disc which disables the update feature on the game disc.
http://www.wii-addict.fr/forum/viewtopic.php?id=2017 The site is in French but all you need to do is download the 1.3 version which is multi-language. It also has added a Game Info option which tells you what region the game disc is and creator etc. etc.
I would recommend users to do both steps above. This will protect you even more from a region brick issue.
If anyone thinks I forgot to add anything let me know.
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Here is a more in depth explanation of why a region brick is possible and how to fix it.
Nintendo has placed region locks on the hardware of the Wii. Making the hardware inoperable when the incorrect region firmware is flashed to it. This is why your Wii can become partially or completely bricked by updating with the wrong region firmware.
UPDATE: It seems that some game disc can update a Wii and semi-brick/Complete Brick it even if your Wii system is updated with the newest firmware.
This is possible if they release a firmware that has been revised but still is labeled the same firmware that was released before.
They must have some sort of other check system available for the firmware that we as the consumer do not see. Like revision numbers of a particular firmware.
Example: Lets say a Japanese Wii has been issued a 2.2J update. They then release a revised firmware of that update but keep the main firmware number (2.2J)
In order to tell the Wii to update the new revised 2.2J firmware they would have to add some sort of rev # to let the Wii know that this update is a revised update of the original 2.2J firmware so it needs to be updated.
So if you have an NTSC(U) Wii system and have it updated to the 2.2U Wii firmware then play an NTSC(J) game disc with a revised firmware higher then what the USA firmware is then the 2.2J revised firmware will update over the 2.2U firmware causing a semi-brick/complete brick issue.
The problem now is that there is no way to tell if the firmware update that is being installed has been revised or not. (Use Wii brick blocker to protect your Wii from this situation)
Brick Issues:
Complete Brick - Wii is bricked completely. Automatically boots to the Opera error screen. All hardware is non-responsive.
FIX: NO FIX AT THIS TIME
Semi-Brick - Wii settings are non-responsive (Opera error screen) Disc Channel is responsive and Game Disc's are still playable.
Fix: Update Wii with a Game Disc (SAME REGION AS YOUR Wii) that has a higher firmware then the firmware that caused the semi-brick (This has to be done with a Game Disc since Wii Settings are bricked and no way of updating Via system settings)
Example:
Mario Strikers PAL has a 2.1E firmware update. Some NTSC(U) Wii owners bricked the Wii Settings with this update. Mario Strikers flashed the NTSC(U) Wii from 2.0U to 2.1E firmware.
Big Brain Academy NTSC(U) can recover the Wii Settings brick by running the update on the game disc which is 2.2U This changing the 2.1E firmware back to 2.2U firmware unbricking the Wii Settings because the correct firmware is now running on the Wii.
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My Theory of why some Wii owners have had a complete brick and some have had a semi-brick is this.
I think the 2.0 U/E/J update had an Optical drive update with it. Which flashed the Wii DVD drive with the wrong region firmware. This not letting the Wii DVD drive initialize during boot up giving the Opera error screen.
2.1 or above firmware updates are only a system update (New Channels/Parental Control etc. etc.) This only bricking the Wii Settings with the wrong firmware keeping the drive operational because it didn't receive an update.
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WARNING TO THOSE WHO STILL HAVE 1.0 U/E/J FIRMWARE INSTALLED...
I wanted to add this information for others because I believe you can still get a complete region brick if playing any game disc that comes with a firmware update and your Wii still has the original 1.0 firmware.
I came across a thread the other day of a member claiming they completely bricked their NTSC(U) Wii with Mario Strikers PAL version. This was the first time I have came across a thread with a member claiming this. I started thinking how this could have been possible and came to this conclusion...
Game Disc with Updates on them have multiple updates on the disc. This is necessary because other firmware updates need to be applied before becoming up to date with the latest firmware. If your Wii firmware is 1.0 it will need to be updated with the 2.0/2.1 and 2.2 update to become current.
Since Super Paper Mario NTSC(U) update completely bricked PAL Wii's due to the 2.0U firmware then more then likley a 2.0E firmware can do this to an NTSC(U) Wii.
I know there is allot of information included in this post and I hope it isn't confusing either. But there has been allot of threads started on this issue and I just wanted to make a guide and an explanation of what the consequences can be by flashing your Wii with the wrong region firmware.
Remember to protect your investment when playing out of region game disc...
1) Update your Wii to the latest firmware version available from Nintendo. (As of now 3.0 is the latest)
2) Download Wii brick Blocker and disable the firmware on the Game Disc...
http://www.wii-addict.fr/forum/viewtopic.php?id=2017 
