Nice going. You bumped a way outdated thread to advise a program you barely know what it does to give an answer that's not exactly what was asked in the first place.
...but since you're new here, I'll take it you have the best of intentions.
Here's the thing: pimp my wii installs a bunch of cIOS on your machine (not cISO's...wich is incidentally an existing but completely different term in wii hacking). Which ones? I bet you don't even know it, and you have them on your machine.
Does it work? Yes. Probably. I dunno. I don't keep track of pimp my wii, or darkcorp, or any other "one click to do everything" solutions...because cIOS are rarely final and are still being developed. More importantly: if nintendo comes out with a new firmware version that stubs some more of their IOS, programs like pimp my wii can become auto brick-your-wii programs (Waninkoko had a program that did that at one point: it downloaded the latest version of nintendo's server and installed that on your wii. Then a firmware update came along, and that program effectively started installing stubs on user's wiis).
Going by your description, pimp my wii also overwrites all the standard IOS with custom counterparts that don't have the antipiracy check in them. Unfortunate for them, other homebrew developers develop their stuff to be used on REGULAR IOS (as in: the IOS you get with a nice, standard wii). It may be nice to know that you can play all sorts of backup discs, but be aware that the drawback is that if team twiizers releases another version of the HBC, it will flat out tell you that it won't install because you've got infected IOS on your machine.
(it's kinda like manually tweaking your car. It's all nice and fun as long as the thing drives really fast...but it will also mean your local garagist won't touch your car anymore because he doesn't want to be responsible for the consequences).
The part where your solution is most flawed is that metroid prime trilogy was only playable on disc. the OP asked for an USB solution, for which there was only a semi-one (it's even in the screenshot: you can play the individual games, not the overall thing. and only on veteran setting).
and yes: was. A couple weeks ago, team d2x properly fixed it (as the previous posters mentioned). With a new USB loader and the correct cIOS, is now playable on USB drive.
...which kinda illustrates my point about it being better to learn a few things and follow this stuff yourself rather than rely on a program that hides its own flaws.