Keep Circulating the Tapes: Neither adaptation has the complete run on DVD. There were a few releases, but they were randomly scattered five 11-minute segment volumes (two and a half episodes each). The 1985 series did get a few VHS releases, but they were exclusively episodes based on books (such as "The Messy Room" and "The Truth"). The entirety of the 2003 series can be found on YouTube at least.
Recursive Adaptation: Some episodes of the TV series were eventually turned into books themselves - twice. Some were rewritten as Berenstain Bear Scouts chapter books, which of course led to some Adaptation Expansion.