Starcraft – What speed are most multiplayer StarCraft II games played at

Against Terran specifically, you should attack the SCV as it is building since that is the weak link. It will go down quickly and then you will not have to worry about it any more.

Zerg players using this tactic will often cancel the extractor as it gets close to finishing and start it over again, to maximize how annoying it is since the health of the extractor resets to maximum every time. In this case, at least he cannot grab both geysers.

Protoss players can build assimilators on both geysers fairly easily, but it's at a cost of 75 minerals each so you will be able to get out an extra zealot and a half that he won't have access to, giving you a slight army advantage first until you get the assimilators away.

Overall, the main thing you have to do against this kind of tactic is make sure that it doesn't affect your macro. Keep building probes nonstop to mine minerals as fast as possible, and possibly go for a 2-gateway or more build to pump out zealots as fast as possible until you've dealt with the issue.

I think what helps to a certain extent. I recommend instead of playing random, pick one of the other 2 races and play a good amount with them, I'd say at least 10-20 real games (if you've never played the race at all maybe play against AI just to learn the hotkeys), and then do the same with the 3rd race. Just going straight into random is just going to throw you off and practicing with consistency is better than practicing many different things at the same time.