DIY noise absorption panel questions... HELP?

So my mother, who is a crafts(wo)man and quilter, just graciously donated a LARGE amount of (very oddly shaped, no two are alike) polyurethane foam and some fabric from among her things of stuff 'n' things. Basically I have a few questions on how I want to go about this 'DIY panels' build...
 
1) Is this even a suitable material? It does not have any special pattern, it's flat- of course, PUR has tiny holes, but will I need to do something to make it more textured? (My idea was to put pleated/wavy fabric overtop) Is it OKAY to wrap this stuff in pleated material? I know it'd help with sound diffusion.
 
2) If I were to do it in this way, how would I determine the best locations in my room for panels? I have something like a gobo that I throw a thick wool blanket over and it does really well, and I'm planning to build a second one soon and get them both permanently fabric'd. I was thinking of replacing the cotton batting inner lining with PUR foam as well. However I do not have monitors and besides test recordings, I have no way of determining the effectiveness of this material.
 
3) What's the best way to fashion pieces to cover corners? Obviously I'd like for this to be both very functional AND aesthetically appealing (because my mom wouldn't let me put this stuff up in HER room in HER house if it didn't look any good :S)
 
4) Any ideas on how I might construct simple, lightweight, wall-hangable and mobile frames for these guys? I was think making cardboard prisms so I could fill them with the oddly shaped pieces of foam, and glue them in then put some adhesive on the back and slap em up.
these questions range for most to least important
 
I know this was really wordy and a lot to take in, but I want this to be a one-and-done kind of thing, and since I have the materials and drive to get it done soon, I think I want to give it a shot. I think the two worst offenders in my room are the back corners and two parallel walls to either side of my workstation. 
Any thoughts?

lots of info on the interwebs
 
lots of DIY places too..
 
http://realtraps.com/index.htm
 
http://www.readyacoustics.com/diy-acoustics.html
 
http://www.atsacoustics.c...ic-Materials--102.html

This information is definitely telling. The studio guy at my church (he actually handed the work off to me O.O) did JUST foam, and while it does a great job deadening most of the sound (it's no anechoic chamber) there's some weird splash back frequency effects from the floor and probably from this big table full of gear in the back of the room.
 
So bats, you said it's best for high-end spot treatment... what kind of material is Rockwool? just standard in-wall insulation kinda stuff? With that in mind, should I even try to use the foam? I have enough to probably make one 5x3 panel and then cover some corners. I have my gobo, which does literally half of the work, but since I have ALL of this foam I would rather put it to some good use inside the room instead of trashing it.
 
Bill, I actually meant to do more for the recording side of things (not presently being a monitor owner). I mentioned those spots in my room where I HEAR wave bounce around, and I was hoping this material would be able to suck up some/most of that absorption, and then I could leave the rest to one or two folding frames for recording sessions
 
Are you guys saying PUR isn't going to be thick/dense/something enough to be as effective as I need it to be?