What is the error? That explains why it can't or doesn't proceed forth. It's the biggest clue for you. As Kees offered the links to directly get the required file for your Win7 type 32 or 64-bit. If you need to, use another PC(friend?) and d/l the file and save to a flash drive/CD, swap over to your PC in some directory and try from there. Check the error online for what it means or goto MS support for common errors.
ive tried everything to dowload windows 7 service pk 1 but my computer will not let me do so always comes up with an error. so so course it does not finish,