You aren't going to be able to do that with an enum, but you could with a class:
public class MyFolder
{
public static String Windows {get {return System.Environment.GetEnvironmentVariable("windir");}}
public static String AppData {get {return System.Environment.GetEnvironmentVariable("appdata");}}
public static String Temp {get {return System.Environment.GetEnvironmentVariable("temp");}}
}
I made it static so you could access like you do an enum (ie MyFolder.Windows
).