I have a new style Glam Tote and I've got a 15" MBP as well and there's no chance I'd fit it in there. Not without seriously scratching it up on the zipper.
I really don't think you'd be able to fit your Dell laptop in it unfortunately.
Consider yourself lucky, I couldn't even manage that! I was upset since I bought it for that reason alone.I have to be very careful to pull it tight to the open end to make sure it doesn't touch the zipper. It can be annoying, but it's the only bag I have that can fit it and is simple to carry.