I'm trying to "try" Ubuntu on my Windows 7 laptop and I installed 12.10 to a USB stick. I changed my boot preferences to boot to USB first. It boots from USB and I get a screen that says "SYSLINUX 4.86 EDD 2012-18-13 Copyright (C) 994-2012 N. Peter Anvin et al" and it just sits there and doesn't go past that screen.
1.) What application did you use to burn the image to the usb-stick? There are several programms out there (xboot, linux live usb creator, unetbootin, etc.), take a look at this site for more: http://www.pendrivelinux.com/
2.) Have you tried another Linux Distribution too?
3.) Have you downloaded the right version (32-bit/64-bit)?
1) Did you md5sum check the downloaded iso? See https://help.ubuntu.com/community/HowToMD5SUM Check the number against the listing in the link for your release listed at http://releases.ubuntu.com under the MD5SUMS link.
2) If using a CD/DVD, did you burn the disc as slowly as possible? See https://help.ubuntu.com/community/BurningIsoHowto
3) Did you select the media check before trying to install? https://help.ubuntu.com/community/Installation/CDIntegrityCheck
4) Did you ever do a "memory check" (another live-media menu choice) on your PC? Doing the above can save you a lot of time struggling with a bad install media.