Leave your receiver in standby mode, you can still access it using your PC.
You can try editing the VU+ folders, using your PC, to remove the faulty plugins, but it's a lot easier just to start again.
You can backup your channel list using dreamboxedit, which you can download from the VU+ Tools section, download the latest version:
http://www.vuplus-community.net/board/forums/vu-tools-settings.10/
Once you have downloaded the latest version, of dreamboxedit, make a new folder, on your PC desktop, and name it Settings.
This is the default name, and location, for dreamboxedit.
Now start up dreamboxedit, click on the Tools heading, and then Options.
Insert your receivers IP address, in the options IP Address box, and click Save.
Now go to File and Fast FTP download, you should now see all the channels, from your VU+ receiver, so click the Save option, and you have these stored.
You can also copy the Enigma2 folder, using Filezilla, the FTP program you are probably currently using.
On the top right hand side, of the split screen, are your VU+ Folders, on the left are your PC folders.
Go to the etc folder, click on the + sign, to expand the folders, and right click, on the Enigma2 folder, and Download, or just drag it to your Desktop.
You can also save other folders/files, if they have been altered.
Now you can re-flash your receiver, with the latest Black Hole, or other image.