I been have reading all your great stories on Capri. Seems like it is a bit overcrowded but still well worth a visit. Anything specifically not to be missed? I do not think I am going to attempt the Blue Grotto, getting into that small boat would be scary for me! ha
The walk down to Marina Piccolo on the opposite side of the island is fantastic. You will be rewarded with great views, some exercise and a good, romantic restaurant near the beach.
Have a great time in Capri! Now, get that courage up and go to the Blue Grotto! There will be plenty of people to assist you into the boat and once inside the grotto, you will see for yourself how spectacular it is to see in person. The city itself is charming and you will find plenty of places to stop for an espresso or a glass of wine. I am expecting to see pictures of your Blue Grotto adventure asap!
Also, try to visit Sorrento after Capri, it is a great city and the hillside cafes are fabulous.
For sure, they have life jackets. I can barely swim myself, so I know how you feel. When we went, I was amazed at the crew for making me feel safe and sound. When you move from one boat to the other, they are literally side by side.
Anyway, you will decide to go or not, do what you feel is best for you! Over the years, I have felt the exact same way about adventures like skydiving, bungee jumping and zip lining! No way, no how! It gives me the creeps just thinking about it. My motto is "I like enough things!"