Hi,
Thank you for choosing Windows 8!
I would recommend you to follow the below given steps to transfer pictures from computer to a flash drive.
a. Plug-in the flash drive to the USB port on the computer
b. Select the pictures that you want transfer it to flash drive
c. Right click on the selected pictures and choose send to option
d. From the options, select the plugged-in USB
e. Pictures will be transferred to the flash drive
To know more about windows 8, refer:
http://windows.microsoft.com/en-US/windows-8/meet
Hope this information will help you.
For any other windows related issue, reply to us and we will happy to assist you.