OK. So I got tired looking up the workaround for installing Ubuntu 10.04 in VirtualBox on Windows 7 and decided to make notes here, so I could find them easily the next time…
When the error message comes up switch to a console. Press Alt+F2 to switch when installing in Virtualbox. Press Enter to activate console and then:
chroot /target apt-get install linux-generic
Once the kernel installation is complete (this takes about 10 minutes or so) type the following:
Press Alt+F1 to return to the installer and then answer “Yes” to the “Continue without installing a kernel?”
The installation will take a while, but should now work.