Yes, google play is available on nook color.
You can not you have to do it on the computer
No. Windows Media player can't play mkv files.
Yes, you can. All you need to do is upgrade your nook.
An HTML file is for web browsers only. It is not a media file at all. But you can have HTML files load media and have them play it in your browser.
Sometimes you may get an error saying that Windows Media Player won't play a WMV files. When this happens, it is because certain files are corrupt or their link is broken so that the files won't play.
To get the Google Play Store on a Nook HD without rooting, you can sideload the Google Play Store APK files. First, enable "Unknown Sources" in the device settings to allow installation of apps from outside the Nook Store. Then, download the necessary APK files for the Google Play Store and Google Services from a trusted source, transferring them to your device. Install these APKs in the correct order, starting with Google Services followed by the Play Store, and you should be able to access the Google Play Store on your Nook HD.
Windows media player.
One player I know is Windows Media Player
let try vlc or any media codec of microsoft.
No. I have searched for a player that will play SP7 files -- but SP7 files are Casio's proprietary music files, only playable by their digital instruments.
you cant.