What Publish & Share options are you choosing? Some options are interlaced, designed to work on traditional TVs, and some are progressive scan, which looks better online or on a computer.
You don't give us many specifics, but generally you should be able to use Publish & Share/Computer/AVCHD with the YouTube HD preset to output a video that will look great on your computer and will not be interlaced (so it won't have horizontal lines through it).
Also, in my books I recommend you preview any of your movies with excellent, free VLC Media Player rather than Windows Media Player or whatever the default player is on your operating system. Windows Media Player in particular makes everything look kind of crappy.
Thanks for the quick reply. I haven't gotten to the publish and share part of my project. I did a render so I could take a look before hand. I'm still viewing within PE12.
Sent from my BlackBerry 10 smartphone on the Bell network.
Your preview may or may not look like your final video. You'll only know if you Publish & Share.
Meantime, right-click on your Monitor panel and make sure it's set to Highest Quality.