You need an 8GB stick these days.
Is there an ISO file on the disc? If so, use that. If not, and bandwidth and download speeds are not a problem, go to the Ubuntu page and grab the ISO file from them:
You probably need the 32 bit edition for a netbook (mine does). If you're not sure, stick with 32 bit.
When you've got the ISO, point the startup disc creator at that file as the image.
i5 4440 3.1Ghz, Asus H87M-E motherboard, 8GB DDR3, 2GB DDR5 nVidia card, 2x500GB Seagate hd, Coolermaster 750W PSU running Mint 16 MATE and Win7
eeepc 1015PX, 1.66 Ghz Intel atom processor, 2 GB DDR3, 320 GB hd, Mint 14 MATE. Fan needs fixing.