Run Windows 7 & 8.1 pro run in virtual environment?

[AMDPower]

Hi all

I currently have windows 7 installed and wanted to run windows 8.1 together concurrently in a virtual environment if possible. So far the easiest option I have is to format my HD with windows 7 and install windows 8.1 pro with Hyper V and then instlal windows 7. The problem is that I don't really want to use windows 8.1 as my main software on my PC and restarting is a pain in the ass.

I don't really want to use a second computer as its annoying.

so I was wondering is there any easy and preferably free way to do this but starting with windows 7 rather than 8.1 pro?

thanks all

 

[AMDPower]

Thanks guys, will try virtualbox seems very good and hopefully will work well.

I need to setup windows 8.1 and visual studio development on both windows 7 and 8 concurrently and also will be using matlab quite extensively.

I was wondering how much ram would I need? Since I only have 6GB at the moment, would it be wise to purchase more?