I created a live USB using Unetbootin (distribution: ubuntu 12.04 ) from the alternate installation ISO, but while booting "try ubuntu" option is not displayed in Unetbootin menu. Is there any way to try this ubuntu distribution without installing ?
Make sure you download the ISO for the Desktop release. If you download the alternate ISO it does not have the LiveBoot "Try Ubuntu" or use the graphical installer.
To download the latest desktop release of the ISO go here:
In the first box select whether you want 32 bit (recommended) or the 64 bit release then click the "Start Download" button.