Yes, you need to change the title of your home page to something that describes your website. It also helps visitors know where they are and About Us when they actually on the home page, is a bit confusing. Also the Title About Us for your content is not good for SEO. Google Spiders place high value on the first Header HTML tags on your Home Page/Index Page and the first +-250 words in your first paragraph. You really need to create a good description and work with your keywords with which people will find your website on search engines and what interest them, in the first paragraph.
Your Header has some white space maybe you can use it for a banner ad telling people why buy from you or maybe a rotating notice showing latest games, popular games etc. In this way you can have what's new, latest games or popular games on each page.
On your central banner ad you could add some call to action function. On the image put words like Read More, Mass Effect 3 The final saga in the trilogy, basically something interesting about each game that will keep you visitor there and clicking away, each image should point to a different game article. It also shows that you know about games to those that play them because you knew that Mass Effect 3 was the last release in the series. Creates trust with your visitors.
On your Top Games page you need some spacing between the image and the video, it feels a bit claustrophobic and I was a bit confused about what that was, a picture or video. It just looked weird. Spacing and scaling the image might clear that up. This can also be an opportunity to add more pages, each game has a page and add links on each page to other game article pages. You could add in game requirements for each game on it's page. So instead on gamers going to other sites to find system requirements for a game, they can find it right there on your site.
On your shop page where people can add to chart, the top navigation bar isn't very descriptive. Try adding to the text links something like "View Assassins Creed" so that you visitor knows when they click there they'll be viewing the Assassins Creed.
Now I'm going to stop before you kick my butt
. Hope you can use this info
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