As fpmurphy's question is alluding to, you need a 64-bit processor with Hardware Assisted Virtualization Extensions.
The cpu flags show what your processor supports. You need either 'svm', Secure Virtual machine (AMD); or 'vmx', Virtual Machine Extensions (Intel). The course materials for an RHCE class I had stated that you also needed 'lm', Long Mode (64-bit x86), and a 64-bit operating system.
i am using acer extensa 4620 laptop of 32bit architecture with core 2 duo processor
I don't know Intel processors, but wikipedia (http://en.wikipedia.org/wiki/Intel_Core_2
) tells me core 2 duo is 64-bit. Not true? The proof is in your cpu flags.