Upgrade to El Capitan

Hi,

I've got used MacBook (late 2008) 10.10.5. It was rather slow and barely operational. I cleaned it as much as I could and upgraded Memory to 8 Gb.

Now I have: Processor 2.4 GHz, Intel Core 2 Duo

Memory 8 GB 1067 MHz DDR3

It works fine and performs well.

I want to upgrade OS to El Capitano because I miss some features like following open browser on other Mac, iPhone or iPad and some other things.

My question: 1. Should I be OK to run it under 10.11.8 a.k.a. El Capitan

2. In case it won't work as I expect ... will I be able to roll it back to 10.10.5 ?

Thanks