Installing a new kernel in Ubuntu.

1) Download the required kernel from here.

2) Copy the tar file to /usr/src/ or untar the file to /usr/src/
                       cd /usr/src/

         tar -xvf linux-x.x.x.tar.bz2

3) Change directory to the kernel
                       cd linux-x.x.x

4) Copy the configuration file of the running kernel from /boot/ as .config
                       cp /boot/config-linux-x.x.x .config

5) Stay in the same directory and give the command:
                      make menuconfig

  This will give you with an user friendly interface to change the kernel configuration like enabling drivers. Just give exit and when asked to save changes give yes.  

6) Compile the kernel
                     make

7) Installs the kernel modules in the system in /lib/modules/x.x.x/kernel/
                    make modules_install

8) Copies the compressed kernel image created during compilation and System.map files to /boot/
                   make install

9) To activate the grub menu open the file /etc/default/grub and comment GRUB_HIDDEN_TIMEOUT=0 and your grub file will look like this :

# 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=30
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

# 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=640x480

# 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"

6) Issue the command
                    update-grub

    This will update the file grub.cfg by checking all the files in /boot/

7) reboot

And voila, now you should be able to see a grub menu which shows all the kernels installed in your system. :)