Eirudo

A lightweight plugin to embed YouTube videos while keeping the correct aspect ratio — all with a simple shortcode.
<ul>
<li>Very simple shortcode. Use it in posts or widgets.</li>
<li>Uses the default YouTube iframe embed, but fully responsive.</li>
<li>Custom aspect ratio if you want a different video size.</li>
<li>Automatically centered, so your video always looks neat in your content.</li>
<li>Lazy load support to improve performance.</li>
<li>100% free — no ads, no trackers, no funny business.</li>
</ul>
<h3>Arbitrary section</h3>
<h3>A brief Markdown Example</h3>
Pros: 
1. Simple and lightweight — one shortcode per video 
2. Lazy load support 
3. Extra parameters available for advanced users
Cons: 
1. Designed for simple embeds only (no playlist support, one video per shortcode)

Simple YouTube Responsive

Perfect

You can add a line to your functions.php to make videos responsive if you're doing your own theme. However, if you're not, this plugin works beautifully and gives other options like lazy load, etc. 

If doing your own theme, add: add_theme_support( 'responsive-embeds' );

Works Beautifully

Easily embed responsive YouTube videos using a simple shortcode. Lazy load included.

Kodetop

WP Youtube Player allow insert Youtube videos on WordPress using a single quicktag <code>[tube][/tube]</code>
Features
<ul>
<li>Easy install</li>
<li>Embed Youtube movies with simple code</li>
<li>Panel for easy configuration</li>
<li>Config Player version (AS2 & AS3)</li>
<li>Support config themes for player</li>
<li>Support HTML5 Player</li>
<li>Support tubePlayer (http://blog.unijimpe.net/tubeplayer/) for play videos.</li>
<li>Generate <code><object></code> code for Feed compatibility </li>
<li>Generate <code><object></code> code optimized for iPhone</li>
</ul>
For insert single youtube video on Post Content or Text Widget you can use ‘Youtube URL’, ‘Youtube Embed URL’ or ‘Youtube Video ID’:
<pre><code>[tube]http://www.youtube.com/watch?v=AFVlJAi3Cso[/tube]

[tube]http://www.youtube.com/v/AFVlJAi3Cso[/tube]

[tube]AFVlJAi3Cso[/tube]
</code></pre>
To insert video with specific size can user width and height:
<pre><code>[tube]http://www.youtube.com/watch?v=AFVlJAi3Cso, 500, 290[/tube]
</code></pre>
To insert video on template, use the php code:
<pre><code><?php wp_youtubeplayer("movie.swf", "width", "heigth"); ?>
</code></pre>
For more information visit <a href="http://blog.unijimpe.net/wp-youtube-player/" title="plugin website" rel="nofollow ugc">plugin website</a>

Simple YouTube Responsive vs WP YouTube Player