I had one of these and I got rid of it about 5-6 years ago. I remember because I replaced it with an 11" MacBook Air 2013, kept it around for 1-2 years and ditched it after its age became annoyingly obvious.
First of all, SSDs work fine in this notebook computer. The drive is user replaceable, you just need to install the mounting rails on the new SSD. If I recall correctly, it just requires a Torx screwdriver. In fact, I still have one of the two SSDs I used in this system: an OCZ Agility 3, now in an external USB 3.0 drive enclosure. The SSD probably added 3 years of useful life; the day I installed it, the system ran better than when it was brand new.
As for RAM, I believe you can install 4 GB of memory modules, but due to system architecture it only lets something like 3.5 GB as user addressable. I don't even know if it's worth paying the money for the memory modules today.
The system itself can run an operating system beyond Snow Leopard. I forget what the last operating system it can run, but you can do an Internet search. It might have been Lion (10.7).
There are a bunch of problems with running such an old computer.
Of course, it's not running a recent version of macOS so built-in applications don't have any of the latest security updates. You might be able to find the last version of a third-party browser (Firefox, Chrome) that can run on the system but those aren't being updated either.
Also, pretty much none of the commonly used apps are being updated: iLife suite, iWork suite, etc.
The system is incapable of handling today's larger data (like editing 4K video files).
A replacement battery costs more than the system is probably worth and it doesn't have a Retina Display or modern wifi. Apple doesn't sell them anymore and you are stuck with third-party vendors.
And yet my two-year old iPhone can do all of this.
If you need something for browsing the web, reading e-mail, watching video, etc. get a refurbished iPad. It's lighter and has better battery performance and is still getting the latest operating system software updates.
For me, I don't see the point in trying to keep using such an old system. And I OWNED ONE.