Keep in Mind

Video is well downloaded from iTunes. If it is rented, make sure it does not expire.
Make sure Chromecast HDMI Streaming Player is connected to TV.
Have Chrome Browser and Google Cast Chrome extension installed on your Computer.
Have M4VGear installed on your computer, which can crack iTunes DRM

Step 1. Convert iTunes DRM-ed movies to common formats with M4VGear

Launch M4VGear and iTunes will be opened automatically with it. Click "Add" button or "Add Files" icon, there will pops up a window which enables you to choose videos you want to convert. Click the "convert" button in the lower right corner to start conversion.

Step 2. Play the well converted video on Chrome Browser

On your Computer, select the converted video & drag it on to the Chrome Browser. You can also copy & paste the path of the video file in the Chrome Browser Address bar. Right click on the video file > Click on Properties > Click on Security Tab > Copy Full video path > Paste in the Chrome browser.

Step 3. Stream the videos to Samsung Smart TV via Chromecast

When Chrome browser starts playing your video file on the laptop, click on Cast icon in the Chrome Browser > Select TV to play the video on the TV.

Learn more in detail form How to enjoy iTunes videos on TV via Chromecast?
Visit here to watch video tutorial on youtube

M4VGear, iTunes movies Chromecast, such a perfect match.

The YouTube Video is helpful:
https://www.youtube.com/watch?v=pNl-qPyKmvc