OK, I just registered after seeing your post. I'm in a some what similar fix. i've been using Mint for some time on other platforms with better success than any other distro. I've been using Linux for about 6 years total. I just got a Toshiba C855D-S5320. I'll tell you my problems in a moment. First, when you power up immediately and repeatedly push F2 until the system starts beeping or goes to the bios. You need to go to the advanced settings and toggle the boot mode from UEFI to the legacy mode and might need to turn off secure boot in the security section. For more on UEFI look here: https://help.ubuntu.com/community/UEFI
My problem is that after installing Mint14 Mate 64 bit, everything works except printing. 2 of the 3 printers I work with on other platforms, HP p2035 & p1006, with the same distro are installed on the Toshiba but printing does not happen. The 3rd is a HP C4240 all-in-one. Mint on the Toshiba doesn't even see it. As far as dual booting, I have no use for Windows so I haven't done that. I've been trying to beat this printing problem but no luck so far. When you boot from a usb drive, try installing your printer and see if you can print before you actually install Mint. I hope someone who knows more will give a hand
As a final note, Mint 13 locks up the Toshiba very quickly after booting.