Thanks for the advice. Actually, the OS partition is (oddly enough) different from the System partition:
There are three partitions (see pic):
1st partition: unnamed - OEM Partition
2nd partition: OS ( C: ) - Boot, Page File, Crash Dump, Primary Partition
3rd partition: RECOVERY - System, Active, Primary Partition
It is this third partition that I would like to either delete or erase and shrink to a small size.
Note: There isn't actually a space between the brackets and the "C:". I put them there so that it doesn't show up as a smiley face.