South of Zurich and Luzerne, the family-oriented Engelberg-Bruni ski area ranges from 1,600m to 2,040m and is accessed via the cablecar on the north side of Engelberg. The sunny Brunni area starts from the mid-station and heads up, so you won't be doing rides down into town. Actually, the only way to snowboard back down to Engelberg from Brunni is an unmarked, unpatrolled freeride, ski-touring route marked in yellow on the map. It officially starts at the bottom of the Sessellift, but you could start from the top behind the northwest side of the Brunnihutte. It heads towards Bergli and Fellenruti before ending up near Hotel Walsegg above town. This route can be tough to follow since there are so many other tracks in the snow in this region heading in many directions and there are several valleys and gaps in the trees. Sure would be nice if they marked the route.
While up on Brunni, make sure to ride the Brunni drag lift up to Schonegg (2,040m). There are marked freeride routes to skiers right of the red piste, and also to the left of the black piste that leads all the way back down to Risti. Before heading to far off-piste to a hutte for lunch, make sure to check if open since they are known to have weekday and poor weather closures.
In addition to the Brunni area in Engelberg, there is a second, more challenging area known as Engelberg-Titlis. And, although not usually mentioned, there is a third ski area southeast up the valley called FurenAlp. FurenAlp has just one lift but it provides excellent access to hikable freeriding terrain.
The base lifts for each of the areas mentioned are on opposite sides of town at the limits of comfortably walking (skiers don't attempt it). There are free ski buses that lap town which you will find invaluable.
There is an off-piste route accessible from the top of the Brunni drag lift. It starts to skiers right of the red marked piste with a 2 hour skin up the Grosser Walenstock. At the summit, there is a great view of Engelberg below. A good freeride route down leads to the small village of Schwand where you can grab lunch at Gasthaus Schwald (Friday-Sunday only). Then just start hiking/skating southeast on the winter hiking trail which leads to Waldegg just above Engelberg. By the way, when picking a freeride route, if you are counting on a hut on the way down, call the day before to make sure it's open -- several are closed on weekdays or if the weather isn't sunny!
While Engelberg boasts to have one of the best apres ski and nightlife scenes in the Alps, you may find it to be quite tame with all the day trippers heading quickly back to the cities. This is especially true on the relatively quiet weekdays in town. At any rate, for apres ski, you can try The Chalet at the Titlis base or the Yucatan (check out the crazy food prices) across from the train station, but don't get your hopes up. For a more unique apres, try the old Gada Bar (plus they have cheap pizza). For nightlife, definitely check out the Eden Bar near the train station, Disco Spindle, the Cave Disco Lounge up at Hotel Terrace or even try the Bierlialp Club where the locals tend to hang out.
To reach the Engelberg snowboarding from Zurich by train, use the regional train from Lucerne into Engelberg (it's really convenient).
Tip - the hotels and restaurants in Engelberg are obscenely expensive. Plus, there is little compelling reason to stay in the town with the mellow scene and base lifts far from the town center. Renting a condo and buying groceries before getting to town is highly recommended. Also, with the unbelievable influx of day trippers during the weekends , it is highly recommended to try coming during the week. Even on weekdays, you'll need to get an early start to avoid the tourist crowds at Titlis.
Note: If you plan to head to Engelberg for snowboarding by train, here are two great options offered by the Swiss train system SBB. First, there is the discounted Swiss Transfer Ticket which provides a round-trip train ticket from an airport directly to the town near the ski area, plus 50% off any additional train or bus tickets. Second, there is the Snow-N-Rail ticket which provides a round-trip ticket from anywhere in Switzerland combines with a ski lift pass for as long as you need at a total 20% discount (see: http://www.sbb.ch/snownrail ).
Overall, Engelberg Brunni is the 11th most popular snowboard & freeride destination of all 68 snowboarding resorts in Switzerland.