after downloading above program looking in system details it tellsme my computer has 512 mb of memory which is correct, it also tells me that 342mb is being used and 168mb is free do you think these figures are correct as it seems to be using a lot of memory , operating system win xp home sp2 any info anyone

That is about normal. My system with 1024MB uses 350MB at idle. XP is designed to use as much as possible and or it needs.

You can also monitor this via the Task Manager:

Right click an empty area of the Taskbar (bottom) and choose Task Manager > Performance

thanks for the information i will upgrade the memory

No problem and thanks for the thanks! Let us know how it goes.