Minimum eyesight standards for Royal Marines as follows:
Visual acuity to be achieved without correcting lenses; 6/60 Right, <6/60 Left.
Visual acuity to be achieved with correcting lenses; Either 6/6 N5 Right, 6/24 N10 left or 6/9 N5 Right, 6/18N10 Left, or 6/12 N5 Right, 6/12 N10 Left.
Refraction limit: Spectacle correction (in any meridian) +/- 6.00 sphere or cylinder, both.
Yes you can, as long as your eyesight is not really bad. An eyetest is part of the recruitment process and your local AFCO will be able to give you more details of the requirements. Alternatively just search the forums as there are quite a few eyesight/glasses/contact lenses threads already.
Watched it myself and enjoyed it. It must be a pain in the arse though keeping them clean and making sure you don't break them. I manage to break my glasses sitting at my desk so you can be sure i'll break them running in the woods!
Yes, you can wear glasses in the Royal Marines, however your eyesight will have to reach a required standard for you to join (which was specified by Ninja Stoker before I managed to hit the submit button). And when you join training it's advised you bring a spare pair and make sure they're cheap ones.