Safe to remove XP from a computer running Windows 7?

"Yes, it should be safe to format your C-drive to put it to better use. That is, Windows 7 does not have any dependencies on your Windows XP installation.

But, warning... make sure that you don't have any accidental data stored to your C-Drive. Windows applications should know that your main drive is the D-Drive (because that's where Windows is installed) but there's that occasional application that ""hard codes"" the C-drive into its path.

The best way to check that you haven't inadvertently stored some data on the C-drive is to disable (or unplug) the C-drive and do a quick sanity check that none of your data is inaccessible. Open your applications and make sure the configuration (and data) is still there. If everything checks out as normal, you should be good to go."

It's not impossible that your C drive is still the boot partition (the boot manager is on it, which then loads windows 7 for you). To find out, unplug your C drive and try to start your computer. If windows 7 starts, you're OK on that part.