I guess it is hard to define the best CDR/CDRW media as my best is not necessary your best. But here is what I learn from reading on the net and my own experience.

There are currently three types of commonly used semiconductor laser head on the market. they emit light at 650nm, 780nm, and a dual laser head emit both at 650 and 780 nm. Most car/home/portable/computer CDROM player use the 780nm laser while most DVD player use 650nm or dual laser. You can find this out by reading the specification of your manual. 
There are two major media , CDR and CDRW, with different chemical composition from brand to brand. Most CDR media reflect light at 780nm but not at 650 nm, (ie. transparent). On the other hand , most CDRW reflects light at 650nm but not at 780nm. It is not difficult to decide which media to use when you think in term of what kind of laser your reader has. For example, If I make audio CD to be played on my car CD player, I would use CDR material. On the other hand, If I intend to play it in my home DVD player with single 650 nm head. I would use CDRW media even thought the program ask for CDR media. I would not be surprised some company is developing a universal media that would reflect light at both wavelength and is re-writeable.
    
Aside from this physical phenomenon, the second thing to consider is how the recording session is handle, in order to share media containing data, the most widely shareable would be, for large amount of data, close disc single session on CDR media (disc at once) because the wide spread of 780nm CD reader. And for small amount of data, multisession on CDRW media which require UDF reader and current Multisession CDROM drive to read. then there is the least shareable I think is the open disc, open session on CDRW media, this kind of disc probably can only be read by the drive that produce it. Then there is all the in between combination of open/close disc, single/multi session, open/close session, on CDR/CDRW media. It would be even more fun when you try to do a combo data, audio, VCD on a single CD.

I wish you can see there is really no best media for the purpose.  

Dan

                         PCBUILD's List Owner's:
                      Bob Wright<[log in to unmask]>
                       Drew Dunn<[log in to unmask]>