Mine did the same sort of thing. You may have to update the Synaptics touchpad driver. Then you will have more options, like adjusting the touch sensitivity down somewhat.
I just got a used inspiron 4100 dell laptop that is running windows xp. if i leave the cursor anywhere on the screen for longer than two or three seconds it automatically selects what ever it is over or anything near it. it is very irritating because i have to make sure that the cursor is not near anything when i am done using it which is hard especially if i have multible browser windows open. it is like the computer is doing what it wants. also, when i am typing in anything like an email or a forum like this, the insert sometimes jumps up a couple of lines and starts in the middle of another typed sentence. i think it's because the cursor was near that part of the paragragh so it inserted the blinking line there. sometmes it just dissapears. can anyone help???