I'll try to describe my problem the best that I can, hopefully it will make sense. I have the same issue every few games, sometimes multiple times in one game. While my latency remains around 20 or so, everything on the map will freeze. I can see HP bars being depleted, however no one seems to be around to cause any damage. Then the game will "catch up" to where it should be, with minion and champion kills registering as well as the current position of where champions are now at. It's frustrating considering I die because I cannot see where the enemies are at, sometimes for a few seconds, while others for a minute or two. Today I dc'd due to it (first time this has happened) and after reconnecting the problem seemed to be solved for that game. I enjoy playing ranked games, and this issue scares me away from them for fear of hindering my team by a possible "freeze up". I hope someone can help me, and sorry it's so long xD
EDIT: I also get some lag in champion select involving my runes, masteries, and summoner spells. The loading wheel seems to just spin for the duration of champion selection.