and certainly not your computer, then it must be the site.  It loads slowly for me too at times.  AAAAAArrrrrrgh, I sometimes could eat a lunch, take a walk, take a nap, and the site is still thinking.....    So it is not just me then.  

There might be a couple things you could try to help give the illusion of speeding things up:

Use Firefox or another tabbed browser (Maxthon, Avant)

open each thread link, original posts and replies, in their own tabs, and set tabs to open in the background.
This way all the links for posts are opening at once instead of one at a time if you just have a single window without tabs.

You can also, use a new tab for posting replies, have it loading in the background, and the tabs help here if you want to refer back to more than one post in your reply.

Won't reallt speed anything up exactly but kind of lets your browser multi-task.

As for when a page seems to take an inordinately long time to open, try stopping it and either hitting refresh or closing its tab, and reclicking the link.  For me at least usually when it hangs what i end up getting is a SQL database error, generally parsing errors most likely from too many querries to the database.

Hope there is something in this rambling you can use.