Help: Can't install theme.

Hey, so i’m on wordpress 3.9.1 and when try and install the zip’d file onto wordpress: Appearance/ themes- upload i get: Are you sure you want to do this?

I’ve managed to install the previous version of wordpress 3.9 and still i get: Are you sure you want to do this?

I’ve tried to transfer the downloaded folder into the themes folder on wordpress via filezilla but it tells me: Failed transfers- (12):

and when i open my website i get: Internal Server error.

I’ve tried to transfer the file using the host itself: Hostmonster.com but when i open mywebsite i get Internal Server error.

I’m not sure what else to do? Wondered if any of you guys could install it if i give you my website details. Thanx 😛