That does not tell you that Ubutu installed into a widows folder will
open independent of a windows system, it does not install grub.

Wubi is Safe

You keep Windows as it is, Wubi only adds an extra option to boot into
Ubuntu. Wubi does not require you to modify the partitions of your PC,
or to use a different bootloader, and does not install special drivers.
It works just like any other application. Wubi is spyware and malware
free, and being open source, anyone can verify that.