the easiest is to have everything on vWii, but it's very limited in size (500MB) and can be risky to install pirated wad files, you can brick your vWii.
That's why users prefer using emuNAND feature, it has a brick prevention (you brick the NAND copy, not your console) and you have few GB (if not TB) of available space to install all games at the same time. plus, it's region free and you don't need to patch your system.
follow the guide I wrote that you posted just above.
it tells you what to do to make a NAND copy and install/play games from it.
of course, you'll want to play
the incompatible games first (like ALL users?)...
incompatible games, such as castlevania, will require additional setup, with illegal to share files, so I can't tell what to do about it.
just play compatible games, 80% of the VC/Wiiware library is a lot to enjoy.
you can install the incompatible ones to vWii, it shouldn't take up to 500MB, and all the other games using the emuNAND feature.
Personnaly, I think emuNAND is the easiest and safest method. but lot of users don't manage to make it work, for obscure reasons ? (don't use a GPT partition, don't use Ustealth drive unless you installed r52mod)