Hi,
   Below is the report generated.Here the main Namespace is SampleApplication.Now when i generate the coverage report i do not want coverage report to show coverage for SampleApplication.Logic.Calculate .
I Use the command filters as below

lib\OpenCover\OpenCover.Console.exe -register:user -target:lib\NUnit\nunit-console.exe -targetargs:"/noshadow SampleApplication\bin\AnyCPU\SampleApplication.dll" -filter:"+[SampleApplication]* -[SampleApplication]*.Logic" -output:out\opencover.xml


Summary
Generated on: 12.07.2011-12.07.2011
Parser: OpenCoverParser
Assemblies: 1
Files: 4
Coverage: 69.2%
Covered lines: 27
Coverable lines: 39
Total lines: 111

Assemblies
SampleApplication.dll 69.2%

SampleApplication.Logic.Calculate 0%

SampleApplication.Program 0%

SampleApplication.Test1 87.5%

SampleApplicationTest.UnitTest1 100%