TimeZoneInfo vs TimeZone

The TimeZone class is new in 3.5 . This contains the information of Time zone in the world.
E.g :
static void Main(string[] args)
{
TimeZoneInfo tInfo = TimeZoneInfo.FindSystemTimeZoneById("India Standard Time");
DateTime dTime = DateTime.UtcNow;
DateTime localTime = TimeZoneInfo.ConvertTimeFromUtc(dt, mountain);
}

MSDN link
Finding the Time Zones

TimeZone

TimeZone(.Net 1.0) is to get the CurrentTimeZone(ie local time zone only) . So based on local time zone only we can convert it into necessary DateTime. But in TimeZoneinfo class helps to convert into DateTime based on any TimeZone in the World.

E.g : for TimeZone

static void Main(string[] args)
   {
       TimeZone tZ = TimeZone.CurrentTimeZone;
       DateTime dT = DateTime.UtcNow;
   }