It depends on your career goals and level of experience with MS products mate. But the most commonly good ones to start at are the 072-....' ones and they come cheap too, and if you are a student registered in an approved institution you get discounts on most of them. here are my current ones, but I'm planing to move to .NET 3.5 or 4.0 later so you can decide for yourself
Microsoft Certified Technology Specialist: .NET Framework 2.0 Web Applications
Microsoft Certified Technology Specialist: .NET Framework 2.0 Windows Applications
Microsoft Certified Technology Specialist: .NET Framework 2.0 Distributed Applications
mshauny
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C#Jaap
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