you cant have all 3 of those in 1 you know
Best is personal preference, some like the 1.8t, some like VR/R32, some like 2.0 16v.
Easiest would be a 2.0 8v of some kind with a MK2 8v head already fitted, then it would bolt right in where the old engine was.
Cheapest would be a 2.0 8v bottom end as above, but you swap your old head over yourself!