If you are only working with MOTOROLA SUPPORTED products that you named, than any modern laptop with at least 4GB or more of RAM will work fine. Obviously since your cables are USB a working USB 2,0 or faster port or two or three.
Windows 7 32 bit is my choice for O/S. But CURRENT MOTOROLA PRODUCTS you named support higher versions of Windows. Always check the README files in your CPS folders for specific requirements.
Now, if you want to program older NO LONGER SUPPORTED CPS based products such as MTS2000, MCS2000, XTS3000, Astro Saber, Astro Spectra, etc. than the requirements are different.
Brands of laptop really don't matter. They are all made in China by the same sweatshop OEM'ers like Compal, FoxConn, etc. Business class machines (e.g. Dell Latitude, Thinkpad, etc) are generally built a little bit better than the garden variety consumer plastic stuff at Wal-Mart at $199.