I have used MyGeneration and the d00dads architecture for several years, and have been a big proponent. The tool is fairly simple and straightforward and the code layer is dead simple. But a recent experience with it has left me a bit wary now. Support for this software is completely non-existent, any forums dealing with it are virtual ghost towns. I am scared of running into another issue later down the road that I cannot fix and being stuck.
I'm looking for something that:
Explicitly supports MS SQL Server and C#.
Simple: No XML schemas! Straighforward tools. Just convert SQL tables to easily accessible objects and collections
Supported: Developer support is essential. A robust forum community with ongoing bug fixes is ideal.
A year or two ago I would have agreed with the answer to this StackOverflow question. Hell, I may have even upvoted that answer. But I just can't justify that anymore. It's dead software and the source code is complicated enough it's not something you can just dive in and update without prior experience.
LINQ to SQL is probably a little simpler, but it's been "officially" replaced by the EF.
** UPDATE **
Here's the 3.5 EF link