"Integer" is the VB
.net keyword for System.Int32. In C# it's "int". They amount to the same thing so it's really a matter of whether you want to use the same name (Int32) between the languages. If you code regularly in both, it could be helpful to use the .net CLR types so it's consistant and easy to switch back and forth. I can't say how many times I have typed "int intSomething" in VB
only to eventually realize that not only are the name and keywords in the wrong order but the keyword isn't correct to begin with. If you standardize on the .net CLR types you'll at least eliminate that problem.
Work smarter, not harder