電腦keyboard完全打吾到字

我用緊notebook toshiba satellite 2400-251, 吾知點解當我想打宇既時候, 每打一隻字, 個游標就自己彈番上前, 當我睇網頁時, 每當我捲落去, 佢就死都要同我鬥, 係都要捲到最頂. 我插左個外置keyboard用嫁, 但係打字既情況都係一樣, 重身裝個windows都係咁.

究竟係咩原因?? 有無方法解決嫁??

更新1:

this is a laptop, a notebook, is not a desktop computer. by anyway, what is wrong with it ?? is it the hardware problem but not located on the internal keyboard?