I AM GETTING THE ERROR E: Sub-process /usr/bin/dpkg returned an error code (1) WHILE I WAS TRYING TO UPGRADE MY PC. i USE ECLIPSE AND IT KEEPS ON CRASHING... pLEASE HELP

I ATTACH THE ERROR

sanju@sanju-Dell-System-XPS-L502X:~$ upgrade    
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages have been kept back:
  aisleriot gir1.2-rb-3.0 gir1.2-totem-1.0 gnome-disk-utility gnome-keyring
  libgck-1-0 libgcr-3-1 libtotem0 linux-generic linux-headers-generic
  linux-image-generic rhythmbox rhythmbox-data rhythmbox-mozilla
  rhythmbox-plugin-cdrecorder rhythmbox-plugin-magnatune
  rhythmbox-plugin-zeitgeist rhythmbox-plugins seahorse totem totem-common
  totem-mozilla totem-plugins
0 upgraded, 0 newly installed, 0 to remove and 23 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? Y
Setting up grub-pc (1.99-21ubuntu3.1) ...
/var/lib/dpkg/info/grub-pc.config: 35: /etc/default/grub: Syntax error: EOF in     backquote substitution
dpkg: error processing grub-pc (--configure):
 subprocess installed post-installation script returned error exit status 2
Errors were encountered while processing:
 grub-pc 
E: Sub-process /usr/bin/dpkg returned an error code (1)