I've managed to sort out how to do this.
In order to open the Build Summary with the build.Uri Property, you must import:
using Microsoft.TeamFoundation;
using Microsoft.TeamFoundation.Common;
using Microsoft.TeamFoundation.Build.Client;
using Microsoft.VisualStudio.TeamFoundation.Build;
The Sample code to open the Build Summary is:
public void OpenBuildSummary(string tfsServer, string tfsProjectName)
{
// TFS Connection
TfsTeamProjectCollection tfsServer = TfsTeamProjectCollectionFactory.GetTeamProjectCollection(new Uri(tfsServer));
IBuildServer buildServer = (IBuildServer)tfsServer.GetService(typeof(IBuildServer));
// Getting the TeamFoundationBuild from DTE Services
var dteService = Package.GetGlobalService(typeof(EnvDTE.DTE)) as EnvDTE.DTE;
var tfBuild = (dteService.GetObject("Microsoft.VisualStudio.TeamFoundation.Build.VsTeamFoundationBuild") as VsTeamFoundationBuild);
var vcs = tfsServer.GetService<VersionControlServer>();
var teamProjects = vcs.GetTeamProjects(tfsProjectName);
var builds = buildServer.QueryBuilds(tfsProjectName).Builds;
// Open First Build Summary from the Query (for Testing Purposes)
tfBuild.OpenBuild(builds[0].Uri);
}
Hope this helps who may need to open Build Summary's.