Check your BIOS. When you power on your computer, break into the BIOS and make sure that the USB is enabled and is the first device in the boot order (ie. USB, C drive, D drive, etc...).
SAVE YOUR MONEY! Don't buy ANY laptop that does not exceed your current needs now, it will only get worse with time. My advice, keep that piggy bank in one piece and keep feeding it until you have enough to get what you really want. Computer speeds keep improving and what was expensive last...