Betts attended Clarendon High School and has a younger brother, Darren Betts - also a talented rugby and football player who played for Salford in the 1990s. Betts was also a former Manchester United youth team player and was featured in an Inside United article in 2008 about former United players who went on to succeed in other sports.
Betts signed for Wigan from Leigh Miners ARL (also known as Leigh Rangers) on 14 October 1986.
At the end of 2001, Betts moved into coaching as under-18s coach at Wigan, and progressed to under-21s, which he led to victory in the 2003 U21 Grand Final. In July 2003, Stuart Raper was sacked as Wigan coach, and he was replaced by Mike Gregory. Mike then appointed Betts as his assistant. Wigan's results improved and they went on reach the Grand Final, only to lose to Bradford. The following season, Wigan reached another final, losing this time to St Helens in the Challenge Cup final. Betts then took temporary charge in May 2004 when Gregory stepped down due to illness. He held the position for a year before he was moved sideways by the club to make way for the appointment of new head coach Ian Millward, who had left St Helens just two weeks earlier and was recruited for his experience. Betts continued to work under Millward until the end of the 2005 season but left in November after refusing to take a post as coaching the academy U21 side.
In January 2006 he took up a post as skills and development coach with Guinness Premiershiprugby union club Gloucester, a position which he left in June 2010, despite having another year on his contract. Speaking about his time at Gloucester, he said "It’s a really passionate place and I hope they can get the success they deserve. I really enjoyed the place, especially the match-day atmosphere and the Shed."
While at Gloucester, Betts emerged as a surprise contender for the vacant England coaching job, which he applied for in March 2010, ultimately losing out to Bradford'sSteve McNamara.
In November 2010, Betts was appointed as coach of Championship side Widnes. In May 2011, he was reappointed to manage Widnes into the Super League in 2012.