Installing Lion from Mountain lion?

Not that I know of, unless you create a Lion USB and install from boot by wiping the HDD first......

 

Unless you have an older model Mac, that came with Mountain Lion, you are stuck with Mountain Lion. Otherwise you should be able to downgrade to Lion via a USB drive with a Lion image on it.

TEG

 

Maybe you can downgrade... maybe not.

It all depends on your hardware. Seeing as your model was released pre-Mountain Lion. Then probably, yes. The easiest way to verify if you can would be to do a Lion install on that computer using a formatted external drive. That is what I would try.

Terry

 

You can use Winclone to clone/image your Windows 7 partition to an external hard drive. Then when you restart/turn on your computer, hold down the option key and go to the recovery partition. You should be able to find something there to restore Lion... Afterwards, you can just restore the image you made earlier of your Windows drive (just run bootcamp first to make the partition).

 

If you don't mind to delete all of your data on your Macintosh partition, you may boot from your media and select Disk Utility. Select your Macintosh partition and select Erase. Then exit Disk Utility and select to Reinstall Mac OS X. Select the partition you just erased as the destination partition. That's all there is to it. It will remove/delete all of your Macintosh data, so you will want to copy any of that data onto an external drive or implement Time Machine to do a backup before you proceed.