Yes, pretty much every editing software offers the ability to composite which is what you're referring to. You can get a free trial 30 day trial of Adobe Premiere Pro on PC or Mac and use the keying feature on there to key out blue or green background behind a subject and replace with whatever you want. If you want to key out something that is not green or blue screen you will need to garbage matte it and worse case scenario: roto it. Adobe After Effects CS5 and above offers something called the roto brush that basically acts as a quicker garbage matte.