Crashing

Hello!
My Minecraft keeps crashing every single time I launch it. When the big MOJANG label and logo appears and there is the red progress bar on the bottom and when the bar is almost there, it somehow suddenly freezes and if I try to close it by pressing the X, it shows a notification telling me that Minecraft Java isn't responding and I could close the program or wait until it responds. I've tried leaving the program open and frozen for a whole day and nothing would happen. When I close it, the Minecraft Launcher pops up again and it says that the game has crashed. In the past 3 days, I've tried at least 30 times to launch it. I even went to the settings and tried the "Repair" option. It didn't work either. The last time it worked was 2 days ago, at midnight when I was pulling an all-nighter. I also would like to know if I am able to uninstall and reinstall Minecraft.