Unetbootin 494 from the provided link is a corrupted package. DO NOT INSTALL IT!
Instead, go into your software center and install unetbootin from there. This is a valid package.
DO NOT format USB stick to NTFS! It will not work with netbootin, and it will not boot.
It's also worth noting that you can NOT boot from USB 3.0. It MUST be 2.0.
Format the USB stick to FAT32, and it will work fine with unetbootin. Unetbootin will automatically make the USB stick bootable at the end of the process.
I've done this dozens of times, and I speak from experience. Follow my instructions and you should be able to install windows 7 from USB, AND it will be magnitudes faster than any DVD drive.
Ubuntu is NOT why your machine is overheating. After 10+ years working on all types of systems, the #1 thing most computer owners overlook, even some experienced users, is PROPER MAINTENANCE!
Depending on the environment the machine is in, you should dismantle the entire machine for a full cleaning at least twice a year.
Looking into the vent with a flashlight will tell you nothing. The heatsink and fan clog from the INSIDE! You have to dismantle the CPU/graphic heatsink/fan assembly and clean it out with a PLASTIC brush, such as a toothbrush.
Linux OS's use FAR less power and resources than windows, and will run a system faster, cooler, and more efficiently. A system that overheats with Ubuntu indicates a clogged or malfunctioning cooling system.
You'd be surprised at the damage a little dust can do to a system, ESPECIALLY if you live in a dusty place, or have pets.
Just like anything else, your car, your house, even your own body, your computers REQUIRE proper maintenance to prevent damage and keep the system performing at it's best!
If your lungs were full of dirt, you wouldn't be able to breath either!