Ubuntu – Error while removing the new kernel 2.6.37

I tried to install the new kernel but something went wrong and I'm trying to remove it now.
The error massege is:

mhd@Tarek-Laptop:~$ sudo apt-get install -f
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  linux-image-2.6.37-020637-generic
0 upgraded, 0 newly installed, 1 to remove and 9 not upgraded.
1 not fully installed or removed.
After this operation, 111MB disk space will be freed.
Do you want to continue [Y/n]? y
(Reading database ... 188780 files and directories currently installed.)
Removing linux-image-2.6.37-020637-generic ...
Examining /etc/kernel/postrm.d .
run-parts: executing /etc/kernel/postrm.d/initramfs-tools 2.6.37-020637-generic /boot/vmlinuz-2.6.37-020637-generic
run-parts: executing /etc/kernel/postrm.d/zz-update-grub 2.6.37-020637-generic /boot/vmlinuz-2.6.37-020637-generic
/etc/default/grub: 33: Syntax error: EOF in backquote substitution
run-parts: /etc/kernel/postrm.d/zz-update-grub exited with return code 2
Failed to process /etc/kernel/postrm.d at /var/lib/dpkg/info/linux-image-2.6.37-020637-generic.postrm line 328.
dpkg: error processing linux-image-2.6.37-020637-generic (--remove):
 subprocess installed post-removal script returned error exit status 1
Errors were encountered while processing:
 linux-image-2.6.37-020637-generic
E: Sub-process /usr/bin/dpkg returned an error code (1)

The previous unsloved error is on this bug.

This is my grub configuration file:

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
RUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset video=uvesafb:mode_option=1024x768-24,mtrr=3,scroll=ywrap" video=uvesafb:mode_option=>>1024x768-24<<,mtrr=3,scroll=ywrap"
GRUB_CMDLINE_LINUX=" vga=792 splash"

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
GRUB_GFXMODE=1024x768-24

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_LINUX_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

thank you for answering.