Choosing Which Programs To Remove From Startup?

I bought a Dell Inspiron 1501 with Vista on it. It has the typical performance problems that have been noted for laptops running Vista. It receives a "Windows Experience Index" of 2.0. The first thing you are told to do to improve performance is eliminate programs from startup. But when I go through the long list of programs, I often can't tell what they do. For instance, I see in this list "Avantquest
Digital Line Detection," "Dell Quick Set," "Synaptics Pointing Device," and "Java (TM) Platform SE 6U5," among many others. Do I just start experimenting and see what happens when I turn them off? That seems very risky. After all, that "pointing device"--that's my touchpad, isn't it? If I turned off my touchpad, I think my computer would be useless to me, because I do not know how to turn the touchpad on again without the touchpad. In short:is there a way to know which programs would be the best ones to turn off? In case it is not already obvious, I do not know a lot about computers. My experience with Vista has been frustrating, because I feel like I do not have the specialized technical training required to make my laptop work well.