I agree, first off, VDJ 4 is a HORRIBLE version. It is way way way different than the version they have today, which is 7.0.5b. Second, you are not supposed to be using HOME for gigs. It is to mess around with so you kinda get a feel for what VDJ can do. When you use PRO, it is totally different. You get access to plugins, skins, video transitions, samples... a whole range of new things.
Also, I would definitely get at LEAST a cooling pad for your laptop. You can get a cheap $25 one that is like a plate that sits under your laptop and takes the and pushes it out the sides/back via some fans... sort of like a heat exhaust system for your laptop.