Several Problems with Laptop

hey TSF,

i have got this acer laptop for a year and there is no problem with my laptop, but recently i have this problem.

list of problem

1) start laptop sometimes stuck at login screen
2) when laptop ready to use, it will jammed by itself
3) sometimes when i am using my laptop halfway, a blue screen will come out saying an error have been found and shut down to prevent any damage to my laptop.
4) when i end task using the task manager, the end process works for last time and now it doesnt work as when i end task a process, it will jammed there.
5) sometimes my laptop the mouse doesnt response to the touchpad on my laptop
6) sometimes it will even say that my windows 7 in not genuine but this windows 7 home premiuem is a real copy and brought it from retailer store
7) sometimes it will automatic restart or shut down by itself

that is all the problem that i have !!!

any good solutions !! ugent reply pls !!! because do not want to reformat laptop again and i do not have BSOD at all !!

thanks =D
riolaw