How to upgrade centos 6.2 to centos 6.5

Upgrade an existing system:

• Insert centos 6.5 DVD
• Press F10
• Select Install or upgrade an existing system
• skip
• Next
• English Next
• U.S English Next
• Select Basic storage devices Next
• Select upgrade an existing system Next
• Select Create a new bootloader Next
• Select centos 6.5 Install

Hence problem solved

After this if you didn't get GUI then

#vi /etc/inittab

Replace 3 with 5 in the last line id:5

#reboot

now you will get the gui

If you feel the desktop is different from the desktop before you used then follow below steps

#vim /etc/sysconfig/desktop

DESKTOP=GNOME

DISPLAYMANAGER=GNOME

#reboot