Angie, your system is very similarly spec'd as my toshiba, I think I'm running 8gb ram and AMD graphics. It does a great job.
RE 4k. At the moment it's really only the go pro hero3's that I know of which can shoot at such high resolution. An even than it's a lower frame rate. It's essentially 4x the resolution of full HD (1080x 1920). Or in other context, a video image made of 12megapixel images per frame. TV's are starting to enter the market at this resolution but typically very expensive (in australia at least).