The former Arsenal star restored Villa's lead after Ciaran Clark's opener had been cancelled out by Rovers substitute Nikola Kalinic.
Nathan Delfouneso doubled Villa's lead and even a red card after 62 minutes for defender Nathan Baker, after a challenge on Junior Hoilett, failed to halt their progress.
Villa, who knocked Blackburn out of the Carling Cup and FA Cup last season, deserved their place in the last 16 despite manager Gerard Houllier making six changes.
Rovers suffered a setback after only 10 minutes when Roque Santa Cruz limped out of the action and was replaced by Kalinic.
Source: PA
Source: PA