What files should go to SSD and what goes to HDD?

At 4G+ a game you wouldn't be able to install many games before filling up a small SSD. I hope you purchased a large SSD.

You can't just move folders to move applications. If you want them on HDD, you will need to install them to HDD. You do this by selecting the HDD during installation as a destination. If you simply move the folder, you will break registry entries and links all through the system.

I'm the opposite as I've installed all my applications to SSD, except for Virtual Machines and Email. All my games are installed to HDD.

 

How big is the SSD? Usual advice is: OS, productivity programs (Office, Photoshop, etc), all programs, games.

In that order of priority.

You shouldn't really be installing more than 1-2 games on an SSD.

 

Yes St1ckM4n is right keep your games limited but that is exact list to use. I would also add that you should use a program such as SSD tweaker to optimize your SSD configuration. If you are not use to chaning the performance manually use that software it will optimize it to run more effectively. There are things such as defrag needs to be turned off, or the drive needs to be in AHCI mode that commonly you wouldnt know but SSD Tweaker does it for you. Check it very important.