problem in installing cent os
I have 160gb laptop. i installed vista in c primary partition which is 25gb and installed ubuntu in d primary partition which is 20gb. A remainig for my data.
Now i tried to install CENT OS by formatting ubuntu. I inserted CENT OS DVD and restarted and i selected to delete my /dev/sda2 which is showing 20480mb and it shown me free space.
but i tried to add partion /boot of 100mb it got added.
but, when i am trying to add / of 3000mb in the remaining 20380mb free space it showing an error message that no free space is available.
i am new to linux please help me out how to install CENT OS and format ubuntu.