Blu-ray players support 7.1 audio formats and high-quality, lossless surround sound. While your high-def disc player and receiver may be able to decode these new surround sound formats, not all discs you play will take advantage of them.
You can choose to store your files on your Chromebook or online with a cloud-based file storage service like Google Drive. With Google Drive, your data is stored in Google's highly secure data centers. The Terms of Service make clear that what belongs to you stays yours..
The app is called Photo Cast and is available for free. After installing the app the only setup required is to grant the app permission to access your photos, and tapping on the Chromecast icon to select the device you'd like to send the photos to. Then, any photos you select will show up on your TV automagically.