Need help - how to label metadata in Win7 for musi with multiple discs

I am having a hard time finding any information on what metadata tag exists to label any music files (MP3 specifically in this case) that come with multiple discs. I have imported some mp3 files into Windows7 and cannot seem to find a way to organize the MP3 data.

For example, on a 2-cd/mp3 set, where the first cd has say 3 songs and the second cd has 5 it shows:
Name #
Blind Man in the Dark 1
Birth of the Mule 1
Mother Earth 2
John 2
Mother Earth 3
Temporary Saint 3
Mule 4
Rocking Horse 5

I know there used to be a way to go into properties and list it as disc 1 of 2, etc...
However, now that I have upgraded to Win7 I do not see that option. How can I distinguish these multi-disc sets???

One other question: I also used to be able to edit my metadata directly from the file in the folder but can no longer do so (only for the name but not the other info like title, album, etc... I now need to go into properties for each song by right clicking, then go to details and can change it there. Is there a way to fix this???

Thanks very much.