some people misinterpret ping statistic very hard. So, ping is how long it takes for a signal to travel from your machine to the server of your choice. So when you get 26ms ping, that's most likely a local server. Now, do you think you will get the same ping if your server moves to the other end of the continent? absolutely not.
So when checking ping, make sure you know what you're checking against (know the location of the server you want to get ping for)
up and down are variable, depending on network load, devices used, etc etc majority of online games are optimized to a point where you're exchaning bits of information very fast, so you don't really need a 5mb connection for stable gaming.
the biggest issue with online gaming is network hiccups and intermittent packet delay. These also depend on many many things, but it is all toghether defined by quality of service. If your online game is a quality product, it will have quality servers that will be able to provide quality service to everyone who connects no matter if it be 12ms or 100 ms pings.