Please help me understand what I am doing regarding dnx451

A few months back I created a web MVC site using VS2015.  When it was created the project.json had two frameworks mentioned.

I immediately removed the reference to core as I knew I would be using framework functions that are not in there.  So my partial project.json looks like

"frameworks": {
        "dnx451": {
            "frameworkAssemblies": {
                "System.Runtime.Serialization": "4.0.0.0",
                "System.ServiceModel": "4.0.0.0"

and

  "dependencies": {
      "Microsoft.AspNet.Authentication.Cookies": "1.0.0-rc1-final",
      "Microsoft.AspNet.Diagnostics": "1.0.0-rc1-final",
      "Microsoft.AspNet.IISPlatformHandler": "1.0.0-rc1-final",
      "Microsoft.AspNet.Mvc": "6.0.0-rc1-final",
      "Microsoft.AspNet.Mvc.TagHelpers": "6.0.0-rc1-final",
      "Microsoft.AspNet.Server.Kestrel": "1.0.0-rc1-final",
      "Microsoft.AspNet.StaticFiles": "1.0.0-rc1-final",
      "Microsoft.AspNet.Tooling.Razor": "1.0.0-rc1-final",
      "Microsoft.Extensions.CodeGenerators.Mvc": "1.0.0-rc1-final",
      "Microsoft.Extensions.Configuration.FileProviderExtensions": "1.0.0-rc1-final",
      "Microsoft.Extensions.Configuration.Json": "1.0.0-rc1-final",
      "Microsoft.Extensions.Configuration.UserSecrets": "1.0.0-rc1-final",
      "Microsoft.Extensions.Logging": "1.0.0-rc1-final",
      "Microsoft.Extensions.Logging.Console": "1.0.0-rc1-final",
      "Microsoft.Extensions.Logging.Debug": "1.0.0-rc1-final",
      "Microsoft.VisualStudio.Web.BrowserLink.Loader": "14.0.0-rc1-final",
      "Newtonsoft.Json": "9.0.1",
      "System.Data.SqlClient": "4.1.0"
   },

I have been thru the recent docs on how to get my project from -rc1-final to

1.0.0 but I am just not understanding and keep getting so and so is not supported in dot net framework 4.5.1, or missing

references.  Again, I know I'm using the large framework, how do I update everything to use the 1.0 release and full framework?

Thanks