Poor performance Windows 2008 R2 under ESX 3.5

We are having performance issues on one of our SharePoint 2010 server .This is a Windows Server 2008 R2 on Virtual environment.
Application keeps running smooth even with top user hits and search crawls. 
But some times even with less than 40 % loads , we get around 100 % cpu usage.
Assuming this is not something custom code , but environmental / configuration issue , I have jotted down few of the top most errors .
Please help me point out the top most culprit of these :
1.  Faulting application name: CcmExec.exe, version: 4.0.6221.1000, time stamp: 0x 339 6 Faulting module name: ntdll.dll, version: 6.1.7601.17725, time stamp: 0x c4 8f
2. The backing-file for the real-time session “WDC.BE95A9B1-DE15-4B78-B923-A12AB70BE951″ has reached its maximum size.
3. MSDTC encountered an error (HR=0×80000171) while attempting to establish a secure connection with system
4. The COM+ System Application service entered the running state.
5. The application-specific permission settings do not grant Local Launch permission for the COM Server application with CLSID
6. The following fatal alert was generated: 10. The internal error state is 1203.
7. Memory Leak : Microsoft.SharePoint.SPRequestManager.GetContextRequest(SPRequestAuthenticationMode authenticationMode)