I have a HP Pavailion G6 laptop which came preinstalled with Windows 8, but I tried Ubuntu and fell in love with it. I removed Windows to get more room for Ubuntu. The real problem arose when I needed to get a program developed by our institute which is currently made only for Windows machines. So I made a partition of 150 GB and tried to re-install Windows with a Windows CD. It gave an error that the disk is formatted by someone who doesn't understand GPT partitioning. Now the only option I know is to use diskpart from cmd, which I don't really want to do because I don't have ext HDD big enough to save all necessary data. So is there any way to convert just a disk partition (I do mean disk partition, not the entire disk) to MBR or Windows-supported GPT format?
Edit:Guys please don't give me suggestions for using VMware or wine.See the comments on first answer for VMware complications and commecnts on second answer for incompatibility with wine.