i downloaded the latest version of itunes and it crashed my computer

I have a Dell Inspiron 530 with Windows 7 professional, my computer was working just fine. I tried to update my iTunes to version 12.1.1, everything was fine until it prompted me to restart my computer. When my computer rebooted, it only boots to the Dell screen and I can either select the set up menu or the boot menu, and when i select the boot menu my computer wont even boot with the HDD, it says that a recent hardware or software change could be the result. Please help