Restoring my laptop

Hello,
i have had a problem with my laptop what happened was i downloaded msn on to my computer and i had outlook express as my mail and when i downloaded msn it replieced outlook express with hotmail and i didnt like it because someone else was using my computer as well and when we went on to hotmail my emails were in with the other persons so when they cheacked there hotmail they could read mine aswell and it wouldnt let me go on the hotmail website as everytime i tryed it said failed to open so i decided to unstall msn off my computer totally and restall it to see if i could get on the website and when i unstalled it i found i had my old internet browers back so i tryed to update it to explorer 7 and it wouldnt let me then i tryed to download msn and it wouldnt let me do that eitha so my friend suggested that i restored my computer to a date and time that my computer would have been workin proberly so i tryed to do this and it wouldnt work i could pick a date and time but when i clicked next nothing happened i also tryed doing when my computer starts up by pressing F8 then going on safe mode and going though the steps and this still didnt work so i was woundering if you could help me with this and if u had any ideas how i could fix it or restore my computer in any other way it would be a great help if you could.