I haven't fully utilized my Softmodded wii which i did using messie's guide
I have been able to play Wiiware and Virtual Console games Downloaded in WAD files
I am fortunate to have a Wii that will play burned Wii Games however I am limited to dvd-5 games because I can not obtain DVD-9s so I can't play Metroid: other M but i can play stripped down versions of Super Smash Bros. Brawl (typically a Dvd9 but can be stripped down) anyways I can also play PAL and NTSC-J games although some of these games are buggy, I deal with it cause well... it's cheap. I have seen people with Emulators on their Wii in which they can play Romz and such but most of these Emu's have no 2 player ability. (Dammit cause I really wanna play TMNT 4: Turtles in Time)
you can still play standard Wii games such as NSMB Wii but make sure your stuff is Scrubbed cause you DO NOT want to Update your Wii.
Hope this helps you out. I'm still workin on how to play GC games that were burned using NeoGamma