I installed Ubuntu yesterday. I partitioned my C: when it was asked to give memory allocation to Ubuntu. The version is 12.04. I was able to install Ubuntu completely:
Ubuntu is successfully installed. Restart you computer.
I restarted and there was no Ubuntu option. Windows 7 also asked for a boot repair. So I did that too. I then wanted to change my boot priority order to Ubuntu but couldn't find it in BIOS section.
I allotted 20GB to Ubuntu and it is deducted from C: but I couldn't see the partitioned drive in Windows 7. Wubi was working fine before on PC with dual boot option.
I used Linux Live key creator to boot my PC through pen drive.