If you are not familiar with any desktop environment in the above link download the top one which is GNOME based edition.Make sure you download the correct ISO image either 32-bit or 64-bit depending upon the processor you are running.If you do not wish to install Fedora on your hard drive you can simply use the live cd to test it OR you can also install it inside your Windows as a virtual machine using Virtual Box and later on can install it on your hard drive with other operating systems.
Click Here To See How You Can Install Fedora Or Another Guest OS Using Virtual Box
You can see the desktop of Fedora in the above image,on the top left once you click on Activities it will display more options with Windows & Applications tab as shown below
Click on the applications tab and you will see all installed apps under it as shown in the image below.You can either view applications category wise or can search it using the provided search box at top right
To install Fedora 15 on your computer`s hard drive click the last icon under the Windows tab with a green down arrow on it as shown below
Once you double click it the Fedora installer will start and you can follow my step by step tutorial here to install Fedora in your computer & dont forget to let us know how do you like the new appearance of latest version of Fedora via the comment option below :)