I intends to install Ubuntu-Linux-12.04-1 in my Laptop (HP Probook 4410s) in which Windows 7 is already installed. I want to make it dual bootable with Ubuntu-Linux-12.04-1. However during installation one of step i.e. "This Computer currently has Windows 7 on it. What would u like to do" the options are two 1 Erase and use the entire disk or 2. Specify partition mannualy. If I opt option 1 it will earse entire disk which I don't want to do so. I have recently installed in Acer make PC the optionwas differnt. If I go through option No. 2 I don't know about option No. 2 it requires root file system to be defined. Is there any one who can give me his or her valuable opinion, please.
The Ubuntu 12.04 install should give you 3 options - 1. Install alongside the existing OS 2. Erase and use entire disk 3. Something else (which is the manual partition setup).
Selecting the first option will let you resize free space on the existing partitions to make room for Ubuntu.
Alternatively you can install Ubuntu using WUBI, the Windows Ubuntu Installer. This installs Ubuntu to a folder within windows and does not require any changes to be made to partitions
With a WUBI install it is still a dual boot system and Ubuntu (if selected at boot time Ubuntu runs natively on the hardware i.e. it's not a virtualised install) there is a very slight performance hit as it is running out of an NTFS volume rather than an EXT4 volume. If you're installing Ubuntu just to try it then it's probably the easiest option as you can remove it quite easily afterwards if you no longer require it.