the volume hangs due to the volume being full run Vrepair and purge deleted files and write changes out to disk.
to run Vrepair is this situation reboot the server and when it says starting MS DOS press F5 this will get it to a dos prompt.
from the C:nwserver type in server -NA
this will load the server with out loading everything and bring you to a prompt. then run vrepair. see how to run vrepair answer