Thank you for your interest in Aspose.Words. I would like just to clarify, Aspose.Words is a class library, which allows working with MS Word documents programmatically. Aspose.Words does not provide any user interface for viewing or editing documents.
However it is possible to create Document preview, for example by converting your document to image, XPS or SWF format. For example , try to run one of Aspose.Words demos and select SWF as a target format:
Regarding viewing Excel and PDF document, you should better ask in Aspose.Cells and Aspose.Pdf forums appropriately. My colleagues will answer you shortly.