Falsepride, for such an experienced CodeNewbie user I didn't see this question coming from you

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I believe that C# and .NET 2.0 is a most excellent start for you. It is motivating to learn an object oriented language with such powers, yet easy enough to build GUI enabeld software.
The dream to build an OS is shared by many. Yet I do feel that as you move along - learning and discovering - you'll find many more fantastic goals.
As your contribution has been of a positive nature over some time, I'll gladly give you a headstart. PM me if you're interested.