when you say format do you mean, dvd or cd? if so put it in your pc and see the disc size, if its larger than 700mb then youve got a DVD and smaller = CD.
Swap magic will work with both NTSC and PAL, so dont worry too much about that, as you choose how you want the disc to run.
You dont need to rebuild it to get the dnas ids rebuildings a whole different process, (its for games bigger than a normal 4.7Gb DVD). Iv found that if you find a DNAS that works for one game it works for the majority of other games you put it onto, so stick with what works!
Memorex are ok to test although some games may not work properly if at all just because of the media they are burnt onto, so keep that in mind, once youve backed up a few games you will be confident enough to use the decent media first time and get it working first time!
You look like youve got all the tools for the job :)
Doing them from the original disc is quite easy really.
You can tell if it is PAL or NTSC by opening the ISO with ISO Buster and looking at the files. I know there are 4 of them, but i only know 2.
SLUS=NTSC SLES=PAL
I hope that you also have found that you will need to mod your PSTwo in order for it to play back ups.
Most of the time testing on Memorex will just waste discs, they are the worst and even if they would work on a good quality DVD they would not work on Memorex. So you are wasting your time testing them on those.