That's typical. You will find that common on older systems. Try 98SE on an old 486 with 32mb of ram. It will run ssslllooowww and load anything ssslowlyyy. There's a few things to try out link reducing the number of things that load along with Windows, adding more memory, using the defragmenter to have the Windows system tool organize the drive for faster read access, and run the system file checker to verify the installatio as well as repair or replace any needed files found damaged or missing.
To run the system file checker type in "sfc /scannow" at the Run prompt off of the Start menu. You will most likely see the prompt asking for the installation disk in order to verify system files as well as perform any repairs or replacements of system files. The disk defragmenter is found in accessories\system tools off of the Programs menu usually seen at the top.
The thing that will see the best improvement would be to increase the amount of installed memory from what a 128mb and 64mb pair of simms? to a pair of 256mb modules. This will have an effect on the overall system performance there. PC133 memory is still available at this time depending on whether the system there runs that or PC100. Review the specifications found on the make and model system board for this information.