I have installed ubuntu on lenovo laptop when i am trying to install windows from boot menu its stil showing the ubuntu

Check out this:
http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows

This gives instructions on how to download, and create a ubuntu bootable USB stick.

http://www.ubuntu.com/download/desktop/try-ubuntu-before-you-install

This will give instructiosn on how to load and install from said USB.

You will need:
A working computer with Windows
A 2GB or larger USB stick
Internet connection

After you've made your USB stick, when booting up the computer you wish to install ubuntu on be sure you have the USB stick inserted when powering it on. When the start screen comes up press ESC to enter the BIOS or boot order. Select the USB stick from within the BIOS boot order menu, or the USB stick from the boot options menu.

Load ubuntu, install, enjoy.

Good luck!

I had so much trouble trying to install windows with the UEFI that I ended up disabling it and used normal Legacy instead ,it took weeks trying to find a solution but I didnt find one .

have you tried resetting all setting to default in your bios.I can do this with my sabertooth z77 .

Have you changed the boot order ?
Restart your computer During the boot process you will see on the screen to press a certain key to enter setup usually the Delete or the F2 key Press and hold that key during the boot up process to enter BIOS the using arrow key scroll down to advanced bios features press enter change your first boot device to cd,press escape then press f10 to save to cmos to restart note this will erase you operating system you will have to have an operating system disk to load it onto you hard drive or create a partition to load another operating system (note after you have loaded the operating system you should go back and change the first boot device to your failsafe or optimized defaults) after windows has loaded your computer will automatically restart it might restart 2 times one to finish the installation the next will be because the operating system is loaded and will boot from your cd during the boot process you will see on the screen to press a certain key to enter setup Press and hold that key during the boot up process to enter BIOS using the arrow keys load failsafe defaults or load optimized defaults press escape then press f10 to save to cmos to restart otherwise it will keep booting from the cd /dvd drive

have you went onto the BIOS to make sure that the boot options are correct e.g. CD DRIVE 1st priority?

hello,

please try with a liveCd (ubuntu/windows)after that it should boot the OS you want to instal.

probably the hard drive in your laptop is gone.
try booting ubuntu in live mode, so without installing it.
when the boot is completed, launch the tool gparted and see if it detects the hard drive: if it doesn't, you need to change the hard disk..

when this happened to me on my Vista machine last year, I freaked out until I accidentally fixed it using by booting with my original Vista boot disc, and choosing 'Repair OS'. Try finding a/your original Windows XP install disc and seeing if it will repair and replace your own Windows boot sector. It would be best to find the one that came with your system, or another like it, but if all else fails, just try a hologrammed Windows XP install CD, but instead of 'install', choose 'repair'.

Lenovo doesn't provide restore CDs... and the S10 don't even have CD drive. Since you install XP in new partition, probably Vista is still there? Try using Vista DVD (I assume you are using external CD for S10). Boot with Vista DVD and choose the repair option if available. If not, you may need to go to Lenovo support to get the S10 restored to original state.