I'd recommend a fresh install of Windows, especially if you're moving from HDD to SSD. It just less likely to create problems. All I had to do was disconnect my HDD, install Windows on SSD, and reconnect HDD. Backed up (moved) all the files I wanted and then formatted the drive.
Cheeck out this article for SSD optimization. Could save yo in the long run.http://thessdreview.com/ssd-guides/optimization-guides/the-ssd-optimization-guide-ultimate-windows-8-edition/
Also check out this article on how to move your Steam games. I'm sure there are different ways to do this.https://support.steampowered.com/kb_article.php?ref=7418-YUBN-8129