Faulty optical drive / Install windows from USB
Guys,
I am having a double problem here, which I could not find a definite solution.
I was trying to install Windows 7 on my MBP Pro 15" Early 2011 running El Capitan. Unfortunately the DVD drive failed as I tried to burn Win7 on a blank DVD. I tried the disc on another Macbook and it works. When I use it on mine you can hear it tries to spin, but after a couple of tries it ejects the disk. So let's assume that the drive broke down after having used it 5 times in 4 years.
I have two options:
1. replace the DVD drive with a new one, £25 on ebay and I install it myself. Cheap solution, but pretty useless going forward.
2. replace the DVD drive with a SSD and effectively upgrade my MBP Pro.
Since DVD are obsolete I would lean towards 2. However I understand that if the MBP Pro was born with a DVD drive, it will be impossible to boot windows from a USB key. I am really confused on the topic.
So my questions are:
a. Is there anyway to install Win7 from USB on my machine
b. following a.: If I remove the DVD drive (and install a SDD) would the firmware just see it as no DVD drive installed and let me boot from USB?
c. let's say the drive is just dirty and not broken: how do I understand that and what do I have to clean?
I know there are posts on the issue but noone seems to point to an exact solution.
Thanks!
MacBook Pro (15-inch Early 2011), OS X El Capitan (10.11)