To add a bit to that, the right of one to make one copy for personal use of properly purchased commercial DVDs is now a part of US law, although proprietary and classified content is specifically not included. Another caveat: The right to copy does not validate the legality of any software used to decrypt and/or make the copy.
"Is there anyway that I can block someone from copying a DVD I make in DVD Architect? "
Short answer, yes.
Long answer, it will cost you thousands of $$ for the first copy for the licensing and glass master.
Rule of content protection: If I can see it or hear it, I can copy it. In other words, copy protection is a complete waste of money.
Here's how I do it - I decided that I am in the video production business - not the DVD duplication business. My DVD's are priced so low ($7.50 each in small quantities) that even though I tell the client that they may make copies of their DVD's, I keep getting more reorders. I even offer to provide them the cover art in a PSD file, but they want me to make their DVD's.