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- How do I install Ubuntu? 4 answers
I downloaded Ubuntu 13.10 iso file. I mounted it and it asked for reboot. After reboot windows started normally. Every time its just asks for reboot and does nothing.
First create a bootable pendrive with ISO using any tool(unetbootin) then boot with penderive from boot priority option in BIOS then you will get the all installation option .
It sounds like you've booted from the Ubuntu disk but neglected to actually install it to your HDD. There should be an 'Install Ubuntu 13.10' icon on the desktop and on the pre-mount screen - it may take some time to get there, nobody ever said booting from a CD/DVD/USB was very fast.
Run through those instructions, then reboot. Here's official docs, if you somehow missed them.
If you've already installed Ubuntu, it's because Windows is greedy and rewrites the master boot record to only point to itself, making it so that it bypasses GRUB and Ubuntu. Typically, this comes from Ubuntu being installed before Windows, but it can happen in other situations.
Burn this .iso to a disk and load and run it after Windows is installed. It'll restore the boot log and you'll see GRUB again and everything should be happy.