.net compatibility

I have Visual Studio 2005 installed in my laptop and trying to covert vs2003 code:
1) I found I cannot compile .net 1.1 code under 2.0, it can only create 2.0 code;
2) Most code get recompiled except one: Form.AutoScale property is obsolete and replaced by Form.AutoScaleMode;
3) I tried to run 2.0 client against old 1.1 server, it went through, and can get some data back; but failed when trying to save info, got exception 'System.ArgumentOutOfRangeException: Ticks must be between DateTime.MinValue.Ticks and DateTime.MaxValue.Ticks'

It seems, in general, recompile vs 2003 code under 2005 is easy, however have to run the code under .net 2.0.

Also find the following article: http://blogs.msdn.com/seshadripv/archive/2006/02/24/538610.aspx