the error message that appears can also poss be a red herring (insufficient memory) to some other driver problem if your system in the main is running ok.
A printer driver for EG. could cause the error but suggest you may have to go into msconfig and the "Services" tab to tick out items to find out. Can be a long tedious process to find poss problem by elimination of programs/services.Pen/paper at the ready.
Have a look in the the computer management lists first,(via start,right click on my computer/Manage then event viewer/applacations list), as it may give you some indication of error record)
photo's hog the ram, you will have to clear the ram and hdd with a defrag or a good ram optimiser. you will find one in the download sector of the pcadviser. tweak-xp pro is neat for ram tune up's and system speed enhancement. also may be worth checking your virtual memory settings. if your system is still sluggish after this, the chances are that your n-ram is holding junk so boot to the bios screen and you are looking for clear n-ram.IF you don't have a setting for this, dissable fast boot as this'll do the same thing.don't mess with any others at this time, once you found it( you may have to spend some time looking) select save and exit. on re-boot you will get a message stating that it is clearing n-ram and then will continue to boot