Crouch scuffed England in front after four minutes and poached a rebound after 74 while Shaun-Wright Phillips, another player hoping to catch the eye of coach Fabio Capello, fired England's second on the hour.
Capello made six changes to the side that lost to Ukraine on Saturday, England's first competitive defeat under the Italian, with Crouch and Aston Villa's Gabriel Agbonlahor paired up front in the absence of Wayne Rooney and Emile Heskey.
Wembley's ear-numbing sound system did its best to crank up some pre-match atmosphere for a match that was effectively a glorified friendly with England already assured top spot and Belarus long since out of the running.
Despite thousands of unoccupied red seats, Crouch raised the decibel level when he got the final touch to Agbonlahor's low cross after the striker had been released by Gareth Barry.
Picked out by Beckham's short corner, the Manchester City player jinked inside a defender and planted a low shot inside the post of Belarus keeper Yury Zhevnov.
With thoughts already turning to the coming months when players will jockey for spots in Capello's squad, Crouch was on hand to slot past Zhevnov who could not hold substitute Carlton Cole's 75th-minute drive.
