MSBuild is a decent build script tool that integrates well with Visual Studio project files (which are essentially MSBuild scripts themselves). There will probably be some learning curve if you've never used it before, but beyond that it's pretty simple to use it to build a .NET project.
Example of building Visual Studio projects using an MSBuild script:
<!-- Compile a C# project and output to a staging directory -->
<MSBuild Projects="MyCsProject\MyCsProject.csproj" Properties="outDir=Staging\bin\MyCsProject" />
<!-- Compile a C++/CLI project and output to a staging directory, then re-sign it -->
<MSBuild Projects="MyCppProject\MyCppProject.vcxproj" Properties="outDir=Staging\bin\MyCppProject" />
<Exec Command=""$(WindowsSDKDirectory)\Bin\sn.exe" -Rc Staging\bin\MyCppProject\MyCppProject.dll $(StrongNameKeyContainer)" />
If you're using Visual Studio Professional or higher, then your can have a solution file that contains both your C# projects and your C++/CLI projects, so it's fairly easy to build everything from within Visual Studio.
However, if you're using the Express editions of Visual Studio, then you will probably want to use MSBuild (or another build script tool), since you can't have a C++/CLI project in the same solution as a C# project using the Express editions, therefore you will want to have an MSBuild script that can compile all of your various projects in one step.
One gotcha that I've run into with C++/CLI projects is with signing. If you need to sign your C++/CLI assembly, then you'll need to add a step to your MSBuild script to use the "sn" tool (should be part of the Windows SDK) to re-sign your C++/CLI assembly after it has been compiled. If you're using a .snk.pfx file, then you will need to use the "sn" tool to first add that key to a key container (with the -i switch), and then you will need to use that key container when you re-sign the assembly (with the -Rc switch).