I'm going to assume that we are discussing Netscape 7.2 profiles here, NOT Firefox or the new Netscape Prototype browser profiles.
The profile names that appear in the Profile Manager are based on the data present in the
registry.dat file, located in the ...\Application Data\Mozilla folder. For "default" profile locations, see:
http://www.holgermetzger.de/pdl.html
You can reset the registry.dat by DELETING it with Netscape OPEN (if you have more than one profile, use the default profile). That will generate a new registry.dat that points to the default profile. This was the fix for a bug in Netscape 7.0 and earlier Mozilla versions but will also reset the registrty.dat in Netscape 7.2 and recent Mozilla versions. See
http://www.holgermetzger.de/efaqgeneral.html#15
Registry.dat is getting bigger and bigger (Netscape 7.0x)
It's important that Netscape is running when you delete the registry.dat file. What that does is to create a new registry.dat that points to the opened profile. All other profiles listed in the Profile manager will then be gone; the "ghosts" and any others as well.
If you have other "working" profiles you can recreate them by creating a "new" profile within the Profile manager with the exact same name and profile location as the "profilename" that exists in Windows Explorer. All instances of Netscape must be closed when using the Profile Manager.... including QuickLaunch, if enabled.
I tried deleting the registry.dat file awhile back, with Mozilla open to my default profile, to see how it works. All went well. ... I just had to recreate my additional profiles with the same Profiles name (AliceW for example) and the same location, by using the Netscape (or Mozilla) Profile Manager, accessible from the Start Programs menu. Details here:
http://sillydog.org/forum/viewtopic.php?p=44519#44519
I have 8 different Mozilla and Netscape 7.xx profiles ... I opened my default profile in Mozilla, deleted the registry.dat with Mozilla running, then closed Mozilla. Next time I reopened Mozilla, the default profile opened automatically. Next, I opened the Profile Manager and recreated my other profiles, one at a time. I then checked for registry.dat... the old one (which I had backed up first) was 7611 kb - my new registry.dat was now a svelt 45 kb
UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.3) Gecko/20040910