User Form

I am trying to write code for an assignment, but I am new to programming and it's not making much sense to me. I was able to create a user form from the instructions I was given. In the wedding date box I need to input a date and have it "determine the year of their next anniversary." I would really appreciate any help and thanks for looking at it

Here is the information I have been given:


15 years - crystal
20 years - china
25 years - silver
30 years - pearls
40 years - rubies
50 years - gold
60 years - diamonds

What I have:
http://i3.photobucket.com/albums/y57.../whatIhave.png

What it should look like:
http://i3.photobucket.com/albums/y57...ldlooklike.png