Dell Laptop not functioning

I purchased a Dell laptop in December for my husband but since he opened it we have only loaded the software that it came with and the thing wants to update 45 stuff but since December he has been taking it too work connected it to the WIFI but the things is just not updating at all. When going into the internet you can search something as simple as news24 but still it does not open anything it is not the connection but the laptop itself that is completely slow. I phoned Russels Brixton as that is where I purchased it and advised them of the situation and told them that i would like to sent it back and cancel the entire thing as i am not going to sit with a slow laptop that i am gonna struggle with and they advised that I can't do that but are willing for me to bring it in and they will sent it in for repairs. This is a brand new laptop which was not used at all yet due to the thing being slow and not even updating how can it need repairs now. I would like to take this back and they can cancel the entire thing from my name. I am not going to pay for something that is of no use to me and since when are we not allowed to sent stuff back when unsatisfied about. I need them to take it back and cancel it with immediate effect it is not negotiable. Angelique Boshoff - ********** 628 - ID ********** 011084