W2 is much more entertaining than the Skyline. Its about 80% singletrack, the only fire road being part of the Wall climb and the link between Whites and the Wall on the traverse above the valley.
Skyline has a huge amount of fire road, its good if you want to get some miles in but nowhere near as much fun as W2. Best to start from Glyncorrwg.
If you’re feeling particularly fit, you could do the same as campfreddie and ride W2 in the morning and then do Whites climb, take the shortcut from Dastardly and Muttley to Perigrine Ridge on the skyline and ride the final Skyline descent (its marked to the right of the trail with a yellow marker at a sort of ‘crossroads’).
Nearly all W2 is open on weekends with some restrictions on weekdays due to logging.