all those spikes on the netgragh point to are alot of data coming from otherplayers/ entitites etc, for a full run down of each colour check out this
http://developer.valvesoftware.com/wiki/TF2_Network_Graph
things like choke and loss would be more probable causes of actual network problems,
from the screeny it looks like it from a custom map - if its not optimized in any way it could be drawing the entire map / player actions continuosly, hence the high entity/player spikes red/green - or it was jsut taken in a busy area
as for fps i have mine capped at 60 via vsync, dont really see the point in running 120fps when my lcd only does 60hz