for the last few days ,when i start Disc Clean up ,its starts and jumps up to two green segments (scanning : compressing old files ) it then freezes and wont proceed any further . any one had this problem before ? windows xp operating system. grateful for any help.
It would be fine if you can run a scandisk (chkdsk in XP) before.
Right click the icon of the disk, choose Properties and go to Tools.
Then choose the Scandisk with all options. Boot. 
Don’t know if this is what you’re referring to:
http://img269.imageshack.us/img269/4348/diskcleanup9ot.png
If it is, have some patience. It sometimes can take quite a while to compact the files. ;D
You could always try using CCleaner instead. 
i used to run Disc Clean up every week at least and it would take a max of 5 mins, now after 45 mins it wont budge from the 2 segment section. you can hear it compressing the files but it wont go any further. may have to download Ccleaner as suggested .many thanks for all your help and suggestions,cheers.