It is a complete pleasure watching computer enthusiasts helping each other out -- it is just awesome!
qhn's advice is spot-on so I'm sure that by now everything worked out fine on this as no activity since December last.
In case it has not resolved, have a look at this other post I made on this forum, as it lists a routine I came up with a while back to resolve "Slow PC Syndrome" that has proven to be very effective:
As for Mr T's advice, I am definitely in agreement that you should do a thorough defrag as that will handle a lot of stuff as well.
The above thread goes into a lot of detail on defragmentation as well as many other points.
Good luck and I hope this all worked out for you.