What is wrong with Windows...?

I have an Acer netbook that came preloaded with Windows 7 Starter. I notice that it constantly 'jumps' around. Like, if I compose an email, it might just suddenly pop back to the previous page and what I've typed is lost. Not just email either, this happens all of the time and seemingly, on any site. This has gotten very frustrating, as you can imagine. Especially if you don't know if you've really sent something or if your info has gone through, etc. Can anyone tell me why it seems to just jump back and forth like this and what I could do to make it stop. Also, sometimes all I have to do is just glide my cursor over the page I'm on and it will pick up on something and pop me on to that page. Really weird. Please help if you can. This is getting very ridiculous and quite frankly, a real pain in the ***! Hehe Thanks for your help!