There are two key choices: to do a fresh install of the OS to the SSD, or to clone the entire OS to the SSD.
Your question sounded to me like a hybrid; you have a new OS on the SSD and want to copy programs off another OS drive. If I interpreted your question correctly, this will not work because the installation process made registry entries, and may have put files in the /windows directory tree, that won't be present in the new OS install.
If you are talking about cloning the entire OS, it's not recommended but it can work. The trick is that you have to clone the drive, not just copy the files, as there are key components that are not visible in the file system, and not in any of the partitions.