Hi communityoil,
The recurring transactions are templates which can be setup if you have transactions which reoccur in regular periods, such as a direct debit for a phone bill which goes out the bank on the same day each month. You can set an interval or date that you want QuickBooks to automatically generate these, and pause or stop the template when needed.
The custom form style template is the design of the invoice which will be applied when you print/preview or email the invoice. You can set up multiple custom templates by going to the Gear icon > custom form style templates, and can also set the default template here.
When you enter an invoice, fill in the appropriate fields and then apply the template you want to use by going to 'Customise' on the toolbar. You will then see the template applied by going to print/preview.
Thanks :)