this problem happened to me when i used the " IS 2012 " for the first time ... firs i thought it is an ISP problem and i tried to survive with it ... no lie i tried as much as i can
... then decided to reinstall my windows again ... was fun when it was fast till i installed " IS 2012 " and then it back again the same annoying problem
then i decided to quit using bitdefender as i got like a 10 months left so i said give it some time till they fix the buggy release ... installed MS security and everything become fine and my internet was just awesome as it should be ... this was 2 months ago ...
now i came back the only thing fixed was the idm download dialogue is a little bit faster .. not fast faster ... when i was using the MS no delay at all in anything .. most of the websites now opens too slow some needs to get reload like 3 to 4 times to start ... while i'm using same websites on my netbook using MS and work like a charm ... 2 months and still have the problem i'm really disappointed of u guys ... this version is totally a fail since it's 3 months now and nothing solved .. and i got to say i'm gonna uninstall it right now and back to the MS free security 
ADD: the only website working fine is your website 
yeah i like to be protected while i'm using the internet but i do like using the internet too 
i tried to not be harsh as much as i can ... but i can't hide how i feel !