Because of the limit of four region changes per computer DVD drive, if someone frequently needed to access both region 1 and region 2 discs on his or her computer (not on his or her TV set), how about using an external drive in addition to the built in drive, with the external drive permanently set to the less frequently used region? That would avoid resetting the region on the primary DVD drive and would avoid the risk of accidentally ending up with it set to the wrong region. For the most part, external drives are very inexpensive, even lower than DVD players that have had their electronics altered to make them region free.
I haven't tested this yet, but I'm seriously considering it.
If anyone can offer a knowledgeable evaluation of the hypothesis before I test it, I'd be grateful for his/her input. After I've tested it, I'll post the results.
Marianna