SSD is it even worth it?

Rightio guys
I am thinking about buying a 120gb SSD
Now I am not the brainiest with computers but I know a bit

I currently have a 64gb and 2trb hdd
The 64gb is a SSD and holds all my windows shit
But is now pretty much full so I am looking into buying a 120gb SSD

So I am just wondering is it worth getting the extra SSD for bf3 shit and my recordings as my 2trb isn't fast enough to hold the recordings from dxtory..