Want to root Using windows which is on VirtualBox.How do i make it recognise the fone when phone is off? I want to root my phone (Micromax A52) and i got the procedure.

But I use Ubuntu for everyday use and now for rooting i need Windows.

I installed it in virtualbox. Now in vbox,the usb device is recognised only if the host recognizes it.

But with the phone off for the flash process, how can i make the guest windows recognise the phone as ubuntu does not recognise
If you have the ADB drivers on Ubuntu, try performing the tasks of installing busybox and su manually as detailed here - http://androidforums.com/a52-all-things-root/586982-how-root-any-android-device-manually.html

The author has used Nautilus on Ubuntu to perform the requisite tasks. YMMV, though upon reading through the thread.

As a workaround, perhaps you could use the root methods detailed in the relevant XDA thread(s) on a Windows machine.