Well, I just bought the cheapest one. I don't think I'll be able to get a internet faster than 100Mbps here in my region very soon anyway...
About the link speed, I'm not sure how to test it. But without the switch, with the cable going from the router ditectly to the PC I get full speed. Which is 60Mbps.
About the cables.
The long one, from the living room to my bedroom is a 15m long RJ45 CAT6.
The cables from the switch to the pcs are RJ45 CAT 5e.
I'm not really sure what these names means. But the first one was working pretty good before, without the switch.
Well, the package says it's CAT5e. I'm not an expert in networks, so I just bought them in amazon.
The long one is CAT6.
About the network adapter, it is set to "auto mode" as it was already before and is recommended by the manufacturer FAQ I linked.
I'm going to attach a print here, it's in portuguese, but I think it's understandable (if it's not, tell me)
Thank you all for the replies!