cant get MS-DOS to open

From: gudism (gudismdesign_at_iprimus.com.au)
Date: 07/31/04 

Date: Fri, 30 Jul 2004 23:58:03 -0700

i'm trying to remove a nasty virus and i need to edit the
registry. after i change 'regedit.exe' to 'regedit.com'
i get a "cannot find exqps.exe This program is needed
for opening files of type 'MS-DOS Application". i get
the same response if i type 'command' in the 'run' part
of the 'start' menu. is there any other way i can get
round this? i'm gettin desperate as i really need to
remove this 'BACKDOOR.EXDIS' virus. any help would be
greatly appreicated. thanks
.