my BIOS setting doesnt show that i could disable or enable it?
That is because the Pentium T4200 does not support Intel Virtualization Technology. Intel Pentium Processor T4200 specs
What Virtualization software are you using?
Windows XP Virtualization on Windows 7 Pro no longer needs VT support in the CPU.http://www.microsoft.com/windows/virtual-pc/support/faq.aspx