what I found confusing was WHY my internet
Unless you're claiming that you're experiencing these issues from PC1 but not from PC2 or that if you make a straight modem connection there's no problem but if you connect behind a router you experience it, then it's not a problem of "your Local Area Network (LAN)".
It's a problem of your "internet connection", which is not "yours" but it's what your Internet Service Provider (ISP) give you.
If the ISP is having temporary issues with backbone networking (wether or a centralized level, i.e. all the users of the same provider regardless of their physical location, or a localized level i.e. all the users of that specific provider within a very specific geographic position) then you're gonna have lag/delays/issues with all the Servers which are normally accesses by that backbone.
I won't go into too many networking details because in the end I'm not an international expert and because it would be too complicated.
I was just saying that while this might not be the cause, it could totally be and it would make a lot of sense. I was trying to explain to you that from a networking point of view it does make a lot of sense and it's not so absurd.
I don't know how the situation is over there in the US, but here in Europe and especially in Italy it's quite a common situation alas. I've experienced it multiple times over the past 15+ years with multiple ISPs.
Let me try to give you a simpler example. Please pardon my extreme simplification of things, it's for the sake of making an example.
Every website you see has a physical location somewhere, and a physical IP address. Most likely it's hosted in a "virtual machine" (VM). A VM is a "virtual computer" inside a super server, that too is of course physically located somewhere in the physical world.
What allows translation this physical IPv4 number (example: 192.168.212.175) into a "readable" address (example:
http://www.playonline.com) is what is commonly called the "DNS". Every ISP has its own DNS servers, and you can use any DNS in the world, not necessarily the ones provided by your ISP. The sole purpose of DNS servers is to allow this "conversion", is to allow you to type a web address in "letters" and have it automatically converted into the real physical IP (it would be quite inconvenient if for every website you wanna surf you had to type the physical IP address, no?)
Now, next step.
To reach a certain Server, i.e. a certain IP, i.e. a certain physical location in the world, there are several "routes", not only one.
When you type a certain address you do not get instant access to that physical PC, there is a "route" that your request follows. You don't see it and it's usually very fast (we're talking about milliseconds), but all your request and all the data you exchange between you and the server follows this route.
As I said there are many possible ones, some faster and some slower.
Which one gets used when you make an access request tipically depends on two factors:
1) The DNS you're using
2) The backbone infrastructure of your ISP
You can change 1) easily by editing the DNS values of your connection and try different ones, but there's nothing you can do about 2).
If your ISP has a contract to use/prioritize a certain backbone channel (a "route" for the data of their customers) and if that ISP is having temporary issues with that certain backbone, then until their problems are resolved, all your "requests" that are supposed to circulate through that "route", are gonna be slow and clunky.
This is pretty common in here for instance, where we have a very complex network infrastructure. When one of those "big channels" is having issues, then part of the web (and only part of it, the part that would normally circulate through that "channel") becomes very slow for you.
Once more: I'm not sure if this is the problem you two guys are experiencing, and I have no clue if this type of issues (which are not that uncommon over here in the old continent) ever happen there in the US where you have quite a different network infrastructure.
My intent was only to say that while I don't know what is the real source of your problem, it
COULD totally be an ISP issue, and it would make totally sense.
The only things you guys can do are:
1) Wait for the ISP to solve the issue (in case it's on their end)
2) Temporarily or permanently change your DNS and see if it makes any difference
P.S.
Note that DNSs are used exclusively in web browsing software like Chrome, IE, Firefox etc. For Software like "Playonline" it makes no difference whatever you set in your DNS field under your network properties.