Ok, I have sorted this out.
Firstly I went through NuGet and added the Telerik.Web.Mvc reference. Once it added the reference i then deleted the folder paths
\\Scripts\2013.2.611
\\Content\2013.2.611
\\App_GlobalResources
Next open the web.config and add the assemblies to the sections sections
system.web/pages/namespaces (note not really needed but added for completness)
system.web.webPages.razor/pages/namespaces/
Next, I set the Telerik.Web.Mvc reference to "Copy Local." Now in most guides this is said not to be done as you dont need to include the references that are already referenced from the main project. However I needed to do all of this for it to work.
Next (as per some other threads) I reset my output path back to the bin\ directory. It previously had been the full presentations\Nop.Web\Plugins output path.
Because I changed my output path to use the bin\ directory I need to copy my dll's and content over to the plugins directory. To do this i just used a few post build events as below. Replace <plugin_name> with your plugin name.
RD /Q /S $(SolutionDir)Presentation\Nop.Web\Plugins\<plugin_name>\
MD $(SolutionDir)Presentation\Nop.Web\Plugins\<plugin_name>\
XCOPY /Y /E $(TargetDir)* $(SolutionDir)Presentation\Nop.Web\Plugins\<plugin_name>\
DEL /Q $(SolutionDir)Presentation\Nop.Web\Plugins\<plugin_name>\Telerik.Web.Mvc.dll
After all this simple closed Visual Studio. Deleted the .suo file (mostly because of the NopCommerce solution bug with VS2013) and re-opened the .SLN file.
Finally when all was initialized did a clean \ rebuild on the solution and Viola we have intellisense.
Not sure what or if all caused it to finally work but glad it did.
Cheers