I am looking for recommendations for an ebook application that runs on Windows 8/8.1 .
You can try the good old ebook reader bundled with Calibre. It's a multiplatform software, so it's available for other systems too, not just for Windows. Besides being a great application (Calibre itself is the swiss army knife for all things related to ebooks), it's also free and open-source.
There is also EPUBReader, it's not a standalone program but a Firefox extension. Anyway I've never used it so I can't tell you much more than this.
I like Readium, which is an extension for Google Chrome. Works best for me.
TxtR is also a good option.
I would recommend Adobe Digital Editions. It's free and will run on 8.1. It also supports EPUB 3. As long as there is no DRM, you can print from there too. It can open PDFs too.