Modchip:
their update blocking is sufficient, it works in the same way as most channels that block updates or starfall.
modchip region free is old style region free and not as good (I reckon about 33% for a chip/old style vs near perfect for a hacked launcher) as some of the softmod methods, while uou can also hardpatch an ISO to be region free there is little point these days with the softmod methods doing it just as well.
If you mean via something like the geckoOS then that is a different matter.
While you could do a straight update and 1:1 isos will still work I really do not suggest it as homebrew is pretty good and some of the things that can be done even better and hacking wii isos is just getting going.
In fact I still suggest 3.2 with starfall and downgraded IOS or IOS modules with the bugs still in it; many hacks for ISOs will not work as they will have broken signing and need to be fixed (which we can not do for those modules with a proper check).
We had a big thread on the subject:
http://gbatemp.net/index.php?showtopic=142...t=0&start=0
Apps of choice:
Note for under 3.2 I suggest using any region changer to go to 3.2 and then follow on.
For over 3.2 (but not 4.0*, if you are at 4.0 without hacks you are out of luck right now) you will need a copy of the original IOS16 ( IOS16-64-v257-prod.wad ) and to install it (it is properly signed and it has the signature bug so we can use it to downgrade everything else. There are several guides to this one).
*4.0 has nothing hacks do not have and I dare hacks do it better.
IOS downgrader (note this is not the same as the cIOS downgrader, that app if for changing firmware version):
http://www.teknoconsolas.es/blog/waninkoko...-downgrader-v10
Wiiscu (used to get all the nice IOS modules with none of the hassle):
http://wiibrew.org/wiki/WiiSCU
Anyregion changer (used to update to 3.2):
http://wiibrew.org/wiki/AnyRegion_Changer
Starfall (a series of nice hacks):
http://wiibrew.org/wiki/Starfall (I suggest all options)
In some ways preloader renders starfall obsolete but I like having both or just starfall myself:
http://wiibrew.org/wiki/Preloader
Preloader is a tool which renames your system menu and loads itself instead. This allows you to load things before the menu, load the wii when the menu is broken (say for instance a bad wad; the system menu has little in the way of detection and problem prevention) and it has some patches so you can hack the menu without installing anything to the menu like you do for starfall.
Note for bad wads you can still do the twilight hack and fix things if you install the appropriate hacks with starfall and leave the twilight hack on there. Bad wads (very rare if you make sure you have good sources) will still mess things up and preloader just makes life easier to repair it.