turns out explorer.exe was using them (shitty windows!!!!!!!!!)
had to kill explorer then delete from dos prompt
at least i got them now and will know what to do in future, cheers for help guys
edit:
this has only helped highlight another problem which i have tried to forget about, a lot of the time when i delete things, i don't get the disk space back!
I think it has something to do with the fragmentation of my disk as in the analysis report it says i have 750,000 excess file fragments. If only defrag would actually get the job done! it always gets to about 27% then ends, saying that not all files could be defragged
any of u guys had anything like this before?