All early GTIs had sunroofs. I bought a new one in 1999. It was one of the first of the 2000MY cars, so had white side repeaters and the DIS between in rev counter and speedo as opposed to where the clock is. That would have had a sunroof, but I ordered it with air con in lieu. It was around 2001 when you got air con instead of a sunroof as standard.
The blue you could be referring to is "Jazz Blue" If you've got leathers with colour coded centers, the car will be a special edition "Colour Concept" From memory they were Jazz Blue, Flash Red, Yellow, Green and Black.