有没有办法安装.NET 3.5 SP1的免费安装？

Basically I want to have our installer also install the .NET framework and any other pre-reqs as neccessary will minimal user interaction, so ideally, just run, accept license agreement and everything else is taken care of automatically. Is this possible? Using WiX most likely with a bootstrapper or some sort.Basically I want to have our installer also ins