There are not a lot of documentaries regarding this period unfortunately. There are a couple of films, however, they suffer from historical inaccuracies. You could watch CROMWELL with Richard Harris. This is a good movie but has some serious inaccuracies in it. The BBC did a show back in the 1990s called THE SWORD DIVIDED which was a series that dealt with the split of a family down Royalist/Parliamentary lines. RESTORATION was a decent movie about, well, the Restoration, but it is more fluff than history. There appear to be some short documentaries on YouTube as well. I hope that this helps.