Depends what you're after I guess. I've been using VideoStudio for years, fairly simple for clowns like me as I'm not doing Hollywood block busters. I just knock out the occasional family DVD or YouTube quicky. In other words just cutting crap out, a bit of music overlay and titles. My PC is a 3 core with 4GB ram of which 32 bit windows uses bugger all of and which is shared with on board video card. I have no problem rendering my video. If you want more ram you need 64 bit windows as 32 bit has a limit, from memory about 3GB.
I've used trials of the pro editors such as Sony & Premier etc but my old worn out brain struggles with them
I'm guessing if you need to ask go for consumer editors like Videostudio, Premier Elements, Window Movie/DVD Maker or the Sony equivalent etc.
Remember to save your work regularly, I do have the occasional program crash which can end in tears
