Try adding this to /etc/hosts:
127.0.0.1 googleads.g.doubleclick.net
I did that a while ago, and that one line made a noticeable difference in my perceived browsing speed.
Doubleclick's not supposed to slow the internet down, but it does in practice, because your average web author is too dumb to follow guidelines as to its usage. As a result, pages hiccup pending its response, instead of rendering properly, then updating when the ad arrives. Google underinvested in its infrastructure, causing their costly ad-server to become a bottleneck. That, combined with failure on the part of your average webmaster to code around its performance limitations, made it a stand-out web irritant!
Fortunately, the above one-line, code-free solution exists! Now, I don't mind a few ads, as long as they don't slow me down. But doubleclick became a bottleneck. So screw 'em! If GOOG had invested, I wouldn't have bothered. But they didn't, so I edited /etc/hosts, and now it's very unlikely I will ever get around to un-editing it.
Oh, I had redirected all the google-analytics, googleads and doubleclick URLs a long time ago, although they seem to come up with new ones pretty often, and yeah, I had experienced horrible stalls and slowdowns prior to that , especially over at HotAir.
Earlier tonight I added google.com to the redirect list.
That ought to be interesting.
Blocking Unwanted Parasites with a Hosts File
It includes the entry you mentioned, and hundreds more.