As far as I know the avira webguard can slow down your navigation quite a bit. I have encounter this problem in the past and noticed that the webguard was slowing only browser that use 1 process per tab (chrome & ie) and was not slowing unique process browser (firefox). I have done a test about 10 month ago, opening 31 random tabs at once in chrome, with these result :
Without Avira Antivir Premium Webguard : 18 sec
With Avira Antivir Premium Webguard : 3 min 35 sec
The webguard was creating a kind of bottleneck. Note that these test have been done with the version 9 of avira and with and older chrome version too, version 4 I think.
Also, when using multiple security software, add all their executable to each one exeption list. This way, if superantispyware do a scan, avira will not scan every file at the same time, and will not prevent superantispyware to remove malware effectively. Hope it help.