I downloaded Ubuntu-14.04.2-desktop-64Bit. I checked md5sum
of the ISO and it's correct.
I tried creating the boo-table USB flash with pendrivelinux
or unetbootin
Windows.
Check disk for defects gives me no errors.
In the boot menu I choose install Ubuntu and get to the choose installation type option (I select Install Ubuntu alongside) => click install and this triggers restart => I get back to the initial menu (Try Ubuntu, install Ubuntu, check disk for defects...).