Lauaki, on his 23rd appearance, scored two quick tries in a dream start for Wigan and winger Iain Thornley then marked his debut with a third try to put Wigan 16-0 up inside 10 minutes. Rhys Williams pulled a try back for Castleford but Liam Farrell restored Wigan's healthy advantage just before the break.
The Tigers struck early in the second half through Oliver Holmes, but tries from George Carmont and Josh Charnley and a brace from Sam Tomkins took the wind out of Castleford's sails despite a late try from Stuart Jones.
The Warriors, who had scrum-half Matty Smith making his home debut, produced a mixed show on their first appearance at the DW Stadium since crashing out of the Challenge Cup and succumbing at home to Bradford in Super League. They lost centre Darrell Goulding to injury in the first half and also lost their way after establishing that early cushion.
Castleford coach Ian Millward was forced to field a patched-up side after losing his new half-back pair of Jamie Ellis and Rangi Chase, with forwards Stuart Jones and Holmes filling in at centre and stand-off respectively.
They looked in danger of being over-run after Wigan's early scoring burst but went on to play their part in an entertaining encounter. The impressive Thornley twice got away down the wing but demonstrated his inexperience by failing to make the most of the opportunities and the visitors took advantage of the let-offs.
Castleford pulled a try back three minutes before the break when winger Williams was put into space by Jordan Thompson. Nick Youngquest added the conversion but there was just time for Wigan to score a fourth try through makeshift centre Liam Farrell after they had kept the ball alive following the sounding of the half-time hooter.
The Tigers battled their way to another try early in the second half when Holmes got the first touch to Ryan Hudson's grubber kick to the line and Youngquest's second goal cut the gap to just eight points.
But Wigan's evergreen centre Carmont produced a strong finish to claim his side's fifth try on 57 minutes and Tomkins took an inside pass from a busy Thornley to go over on 66 minutes.
Tomkins then got Charnley over for his 31st try of the season and, after gallant Castleford pulled another try back through Jones, Tomkins grabbed his second after collecting Harrison Hansen's pass by his bootlaces.