Personally , since LMDE only requires 512 MB of RAM ( 1GB to run comfortably ) as I have read here > http://blog.linuxmint.com/?p=2809 ,
I would only upgrade the SSD and let it fly. You'll be impressed ! I was and at the time I only had 2GB Ram and a 320 GB HDD and it was fast than .
rproffitt commented: Always upvote for other boot media. +10
rproffitt commented: The word gets around about this. +8