Hello and welcome to the forums!
Can you first fill up your system specifications by following the tutorial below?
System Info - See Your System Specs
This will help us solve your conundrum.. without your system specs we wouldn't be able determine why you're getting the results you're getting...
EDIT:- Video rendering/encoding using x264 at 1080p is a very very CPU intensive task that would run like molasses for any system with less than a quad core or i7 sandy bridge or newer. As a point of reference my own aging laptop which is nearly 3 years old now has a Core 2 and takes 6+ hours to render/encode a 1 hour 1080p 24 fps movie clip using Handbrake