George W. Bush Tears Up Dance Floor at Nephew's Wedding

George W. Bush doesn't spin himself right round when he's getting down on the dance floor, but the ex-President's definitely got moves ... just ask his nephew's new bride.

Dubya attended Pierce Bush and Sarahbeth Melton's wedding this weekend in Colorado Springs, where 43 was seen dancing up a storm at the reception after the couple said 'I do.'

Bush had no shame in his game while busting out some sorta dance -- the short-circuiting Robot Running Man, maybe -- with Sarahbeth to 'You Spin Me Round.' She was definitely spinning, but the ex-Prez stuck to a simple full-body shake. Classic.

Watch to the end of the clip ... looks like he was attempting to get a Conga line started.

Gotta say, this reminds us a lot of Prince William's '90s moves in Switzerland last year. When the right tune hits ... some guys just can't hide from the beat.