I downloaded Ubuntu Desktop 12.04 LTS 32-bit. Used the Universal USB Installer, but it wouldnt recognize the file. It was a clean download and I'm quite sure that its not damaged. Any suggestion or any other software you'd recommend?
Try Unetbootin ,select the appropriate installer file based on your Current OS and also verify the md5sum of ISO before using it.
A suggestion , see screenshot
I faced the same problem in my windows 7. It doesn't recognize not only ubuntu iso but also all other ISO I have.
I would recomend, LILI.
From here you can get it.