I inherited a crappy laptop (4 core atom processor, with 4 gigs of RAM, fear the power!) because Windows was running slow on it. I decided to try different Linux distros booting from a USB and had no issues. I literally ran the system for months off of a Sandisk USB drive, and it was faster than the spindle drive in the machine.
My recommendation is, don't cheap out on the USB drive. No-name drives are fine for word files, but the performance increase from a Sandisk, Samsung, Kingston or equivalent is worth it for any media transfers and will work fine for a bootable Linux.