Current generation PCs with Motherboards allows to boot and install Windows or non-windows operating Systems from the USB drive, if your system supports booting from USB drive (check your BIOS settings) rather than burning ISO image to CD/DVD you can burn them directly to USB Drive with ISO to USB freeware program.
Using ISO to USB
Download the program, install and run it on your Computer. From the app interface, select the ISO file via Windows Explorer (make sure you plugged in USB drive) and click “Refresh” button to appear its drive on letter on the program window, (remember USB drive capacity must be larger the ISO file).
Choose the file system from FAT, FAT32, exFAT, NTFS and select the bootable option if you’re burning windows bootable ISO image and click “Burn” button.
ISO to USB works on Windows XP/Vista/7 (32bit/64bit) .