Microsoft Windows XP needs at least 256MB RAM to operate at a reasonable speed. Your processor is more than sufficient.
Do remember that DISK SPACE is not the same as MEMORY (RAM). However, both use the terms Mega and Gigabyte.
I was hoping that everyone would have cottoned on to the 512 MB 'theory' as Windows '98 & ME have a 512 MB maximum before changes need to be made to the Vcache settings in system.ini
If the manufacturers would do the same then the same box with a 512 MB RAM module would be sufficient for 2000 / XP.
In manufacturing terms this would produce savings, as there would be no reason to produce modules less than 512 MB and so all the handling and freight charges would reduce too.
Same for video cards. No on board sound or video just a minimum standard of say 128 MB video cards so that there is no problem with sharing memory for video.
Anyway my advice is to stick to the 512 MB minimum as it is common to '98, ME, 2000 & XP, as when I took ME off the system and installed XP, my computer had 256 MB of SDRAM, and there was a
huge increase in performance as soon as I doubled up from 256 MB to 512 MB.
As I bought the RAM modules at a computer show direct from a manufacturer, I bought three 256 MB modules and found that that was more than enough for my use of the computer even though the mainboard can hold three 512 MB modules.
With three modules there is always the possibility to run with two, so I regard the third one as a 'spare'. (No point in waiting until the modules you use become unavailable.)
This computer says 'Designed for Microsoft® Windows® 2000 Professional' on the front label so the capability for the mainboard to hold three 512 MB RAM modules reflects the design.
If a machine has sufficient RAM then taking things out of the start-up, and generally fiddling around with all manner of settings becomes a thing of the past.
I don't even defrag these days, it all happens ... automatically.