you can use wii game manager to identify which IOS are used by the games you have... however...it is irrelevent as that only matters for discs launched via disc channel. USB loaders run games on cIOS which, for most people, are based on IOS56 and IOS57 and installed in slos 249 and 250. these two IOSes can run almost all games. The system menu version is also irrelevent.
if needed, you can use modmii to build the cIOS for slots 249 and 250. d2x-v8 or v10 are the ones to use. Modmii link is in my sig. if you modded your wii recently though, you probably already have something in the cIOS slots that will play those games.