You'll definitely want to purchase the Desktop (CD/download) platform.  Based on what you've said, you'll need TurboTax Premier (to cover the investments).  

The Desktop program allows for up to 5 free federal e-files.  You can actually prepare unlimited federal returns, but only e-file 5.  With the Premier program, you'll get one free state tax preparation download.  Each additional state tax prep program is currently priced at $39.99.  You should also know that to e-file a state return using the Desktop program, you'll be charged a $19.99 fee.  Of course, you can always mail a state return and avoid that additional cost.

I'll share the link below for ordering TurboTax Premier:

https://turbotax.intuit.com/personal-taxes/cd-download/premier.jsp

PS:  You can also purchase the CD or downloads from multiple retailers, both in-store and online.  And you'll likely find better pricing there.  

I'm going to add this other info comparing the Online platform and the Desktop program, just FYI:

"What are the advantages of the TurboTax CD/Download software over the Online version?"

https://ttlc.intuit.com/replies/4535178