Dan did you read my post? You say that 15% seems like an appropriate number for when XP slows down, yet you dont even have 10% of either drive free. You wonder why your system is slow, yet I have explained it and now so has someone else, yet you keep jumping that point. You stated that you have 16GB of 150GB and 13GB of 230GB. Neither of which is the lowest recommended amount to be free for a drive before XP starts to slow down. That is not 15% of those drives free, let alone any number higher.
I already said that you ha to clean some of your storage, Thomas has now backed me up and yet you continue to ignore the 1 factor that is the common denominator. You are either going to have to try and delete some of your data to see if that helps or live with it being this slow cause you used up to much storage and the system has a hard time working with the amount you do have. Until you try, there is no way to solve such issues that you are having.