I cannot repro the problem - I have no problems with viewing any website in IE10, and no problems with previewing my own sites.
EW4 produces HTML, IE10 renders HTML. The only problem I can guess at is you are not using a server to preview pages that use server-side scripting (asp.NET, PHP etc).
Have you set Site->Site Settings - Preview to use the Development server for all pages?
Or perhaps your site uses HTML that is not compatible with modern browsers- a link to a faulty page will enable us to check that.
Does previewing in other browsers (FireFox, Safari) present problems?
Ron Symonds
Microsoft MVP (Expression Web)
www.rxs-enterprises.org/fp