Is this DVD or BD or a movie file? If the latter, is the file pixelated before you send it through HB?
If DVD or BD:
-have you tried one of the presets or are you tweaking things yourself? If the latter, try a preset. Since this looks like the Columbia logo, try things by rendering only the first 5 minutes or first chapter (until you solve the problem, rather than rendering the whole show or movie)
-try CQ of 20 or 19
-are you messing around with height & width? This looks like a black & white movie which may or may not be formatted for widescreen (a lot of old B&W are not). If you are trying to- say- fill your screen edge to edge, you might be setting something wrong there. Again, try a preset and don't change anything manually and see what you get.
My suspicions are that you are manually tweaking the settings so a preset is probably going to fix the problem. I'm guessing you're going for (small) file size over quality and are making decisions to overdo that goal.
How old is that laptop? Can it play back h.264 encoded HD? Try playing back some h.264 encoded video on it that you know looks fine on other hardware and see if that laptop has the horses to play back your file. Or take this pixelated file to potentially better hardware and see if it can play back (try it on an iPhone, iPad, Apple TV or other). If you have an HDTV with a USB jack, copy this file to a Flash drive and see if the TV plays it back without pixelation (that would just about confirm the laptop is too weak for h.264 playback).
