comboboxes in userform, submit buttons opens outlook.

Hi, I created this userform and looking to make a few changes to it. The checkboxes you will notice in the attached file I want to replace with comboboxes with the same labels. I tried several different options but it didn't work.

Also, is there way so when the submit buttom is clicked, it opens microsoft outlook and the information submitted would be transferred in an email? Any help, suggestions would be highly appreciated.