Im a new to linux, my friend gave me this installer, Linux Ubuntu
I have just one question, can i have 2 different OS, i mean one from windows and one from linux... how can i do it, is it safe?
My disk is partitioned into 3, what i mean, can Linux installation can harm my windows file system. Do i have to change the file system of my HDD to be compatible to linux?
You'll need a EXT3 (For example) partition for Linux, and you can keep the NTFS one for Windows. However, you have to re-write the MBR (Master Boot Record) to let it boot, and install a boot loader such as Grub to give the option to boot the other partition.
Linux installers generally do both of those, though.
Your best option is getting a disk partitioning software (I use Acronis Disk Director Suite 10.0). This is very easy to use. You just install it in Windows and tell it to create a partition in your hard drive. Then install Linux in the empty partition and there you are! (By the way, Acronis' includes a nice boot manager too )
yes you can, like mr. djax said you just need a disk partitioning software to make the linux partition (at least two: one with the size you want for the system and other of about 512mb for the swap space), for the integrity of your windows filesystem you don't have to worry, if you use ntfs from linux you can set just read-only privileges and then you will read any file of your ntfs partition but will not have access to write on it
I would actually suggest you use a virtualisation software (e.g. vmware) to achieve the 2-OS scenario. In such case, you don't have to restart your computer for your alternative OS. Since you are new to Linux (ubuntu), I would recommend you to install it within vmware so that you can simply delete it off if you don't like it.
The bad point about this is that you need a relatively powerful PC to achieve so.
Yes i partitoned my laptop with 2 15gig partitions 1 with Windows XP and 1 with ubuntu it uses grub at startup to detect the two different OS and it works perfectly fine.