my virtual bx does not responding after that(image given),it showing like that for half hour…
You can cancel the current process. Try again and do let us know if you face the same issue.
You might try VMWare as well after uninstalling Virtual Box if you are unable to proceed.
Kindly delete your ubuntu server and create one more because this seems to be a starting error.
I also faced the same issue while installing virtualbox. Make sure you have your virtualization enabled in the bios in settings. Restart your computer. If then also the problem persists, then kindly create a new ubuntu server.