Lightworks is completely free and not bad, runs well on my old laptop with win7 also. it's got a learning curve. and the free version only outputs 720. but it is completely free and full powered.
Look for anydeals on cyberlink powerdirector (it's like 100 to buy I think so cheaper than most) I use Power Director for all my videos now. I got fed up with premiere. But I started with lightworks. I just wanted 1080 output for my youtube videos.