I am also having huge trouble loading the like pages you mentioned. I believe it started after immunizng with spybot but can't be certain. I've tried running a different profile and deleting all sorts of stuff to no avail.
You could try running firefox in safe mode to isolate add ons and stuff and see if it still hangs. If it does you can then try a new profile and see if it hangs. These are the things I've tried but as mentioned still no luck. Somehow the browsers must be blocking ebay and other like sites.