Need a Windows tablet as a replacement for my netbook

Required

• at least one full-sized USB port
• 6+ hours battery life
• Windows. should be able to attach an optical drive to read and rip CDs

Would be nice

• Ubuntu-friendly
• lightweight
• stylus support for writing

Usage

• mostly reading PDFs
• occasional typing and internet

I'm in Russia, so getting a China tablet shouldn't be too hard.

edit: Right now, one that seems to fit is the HP Pavillion x2