According to the audiocommentary of Back to the Future III, Robert Zemeckis wanted Reagan to play the mayor of Hill Valley in the third movie. Zemeckis approached Lew Wasserman, who was then the chairman of Universal and Reagan's former agent, to broach the idea of returning to acting. The commentary asserts that Reagan seriously considered it, but decided against it.

Back to the Future was one of Reagan's favorite films and he even quoted the film in his 1986 State of the Union address.

I haven't seen anything that indicates that he did, and it based on the importance he placed on appearances it is likely that he would regard it as degrading to the office of the presidency. Additionally, his mental acumen would have prevented a post-presidency return to acting. In 1994 he wrote a letter acknowledging his Alzheimer's disease and many on his staff noted a decline in his abilities in the later years of his presidency.

Additionally, there is the issue that many of the movies of the late 80s and early 90s would be too violent or sexual for Reagan. He took a very conservative view of what was appropriate behavior (shocking I know), so this would have limited the projects he was interested in. For example, in his diaries he described An Officer and a Gentlemen as a "great story ruined by too much violence and sex." Reagan's taste ran much more towards the sort of movies he made in the mid-twentieth century, which Hollywood had largely moved past once he was out of office.

None of this rules out a return to acting, but as I said I've yet to come across anything that indicates it crossed his mind despite spending plenty of time doing research in the Reagan library and reading most of the creditable biographies about him.