Working with registry in Windows 2008/7 startup repair

To access your windows registry in startup repair, you need to load it first in a temporary key then run regedit.

Suppose you want to edit the HKLM\Software key, load it with the following command

REG LOAD HKLM\Tmp D:\Windows\System32\config\Software

Where HKLM\Tmp is the target temporary key and D:\Windows is your system root

Now run Regedit and navigate to HKLM\Tmp.
When you are done unload it with this command

REG UNLOAD HKLM\Tmp