Windows 7 - 4GB USB - Won't Create Partition Primary

I hope I put this in the right spot.

Okay I am trying to make bootable USB so I can reinstall my Windows 7, but when I get to the step to create partition primary, it tells me there is insufficient space to do so. What's up with that? I really need to get my laptop back working before the 14th, because I am going up to my grandparents' house for the summer and would like to bring my laptop with me. I also don't want them to find out I broke it so...heh.
Also, I've tried burning the ISO to a 4GB DVD disk with ImgBurn but every disk I do gives me an error, and I only have 3 DVDs left and I don't want to try again because I don't want to waste them. I actually just went out to buy this USB so I'm really upset that I'm having issues with it. ):

Thanks for the help!

have you tried following the instructions in this tutorial

USB Windows 7 Installation Key Drive - Create

What File system are you using on the key?

This small utility is the easiest method to write the ISO to flash stick. Just place Windows 7 in the dropdown menu: Universal USB Installer – Easy as 1 2 3 | USB Pen Drive Linux

Where did you get the ISO? If you have further problems you may need to download another, or check the HASH against official Windows 7 HASH.

Tips for getting a perfect clean reinstall of Windows 7 based on hundreds done here: Reinstalling Windows 7