Yes...in order to install the homebrew channel, you'll need to softmod it. And the latest firmware isn't capable of hacking without a retail version of Smash Brosh Brawl (NTSC only) or Lego Indiana Jones (either PAL or NTSC).
Are you sure of your firmware? As Burton mentioned, the "U" in 4.3U indicates that it's a NTSC wii. And it indeed requires NTSC wii games.
Well: if you softmod it, there are some tricks to get out-of-region games to work. But like I said: to softmod it, you'll need one of those retail games first.
yes im sure that it is U i bought it on GameStop in USA California. and fortunately i also have SSBB USA version i also bought it when i bought my Wii
QUOTESo basically, unless you can get NTSC games, you will need to soft mod it... which requires an NTSC or PAL version of SSBB, or NTSC Indiana. However, by saying this I'm not telling you to go and do anything illegal nor am I implying it...