Can you please edit the title of your original post to say "solved"? This is useful both for people searching the forum in future, and to save time for people looking at new posts.
In the case of virtualbox, it's actual better to install the latest precompiled binary from the VBox website. The kernel-source is still needed.
Yes. It took a really long time to build, and that too with processor at full use, even though this computer is of reasonable configuration. I was worried that the motherboard / cpu may get too much heated and damaged.
I'm sure your hardware can cope. Normally, it's not a good idea to install third-party binaries, but in this case it's a good way to get the latest version from a trusted source, without the long build.
