Okay, I use Deep Freeze on a regular basis and I can tell you this:
There is NO WAY to remove it from inside Windows unless the system is in a thawed state and you use the same installer file to remove it. Deep Freeze by it's very nature prevents ALL changes to the system - and the 'problems' you have experienced in your first post are exactly what Deep Freeze is designed to do - keep the system in the exact state it was in when you installed Deep Freeze. Deep Freeze was designed to keep out even the most determined hackers/kids and it is one of the best programs in the business. If you know the Deep Freeze password, simply hold down the shift key, double click on the deep freeze icon in the system tray and then set deep freeze to "Thawed" (you may have to reboot). Then, you can simply run the deep freeze installer which will remove deep freeze.
I should also note that the following will not work if there is a BIOS password and/or you cannot boot from CDs on the machine. Deep Freeze prevents BIOS password crackers from working for obvious reasons so if there is a BIOS password you are pretty much stuffed.
Otherwise, you need to do the following:
Download UBCD4WIN and burn it to a disc. Boot from this disc (it may take a while, be patient) and open the registry editor. Search for "Frzstate2k" and remove any entries related to it. Also do a search for just Deep Freeze and DeepFreeze and remove anything related to that.
Also remove the Faronics directory from C:\Program Files
Navigate to C:\WINDOWS\system32 (still in UBCD4WIN) and open the drivers folder. Delete all DeepFreeze's drivers which may be DpFrzLo.sys, DpFrzHi.sys or just DeepFreeze.sys.
If you boot into Normal Mode you should no longer see the "FrzState2k" service in task manager and deep freeze gone.
Some other files which you should run a search for are these:
persis00.sys
persifrz.vxd which usually resides in c:\windows\system\iosubsys\ (this file is actually all Deep Freeze is, was and will be - however this file is harmless without the C:\Program Files\Faronics directory)
PLEASE NOTE:
To attempt to remove deep freeze on a machine that is not yours (i.e, at school) is NOT ALLOWED. It would violate the acceptable use policy as this is tampering with equipment that is not yours and would most likely see you expelled or fired. I cannot stress this enough!