There are several different guidelines and checkpoints that web authors can use to make web content accessible.
Question: Which one is the best?
Answer: It depends.
The California Community College system is under state law to comply with the accessibility requirements of Section 508 of the Rehabilitation Act of 1973. The obligation to allow participation and provide access to information was set forth in Section 504 and Title 2 of the American with Disabilities Act. Section 508 provides guidance and direction to meet these obligations when using electronic and information technology - it is not just about webstites.
Section 508 identifies standards for making content accessible within a web environment. Most of the checkpoints include the same issues that we have been discussing.
The Section 508 Standards for Web content: http://www.access-board.gov/sec508/guide/1194.22.htm