Accessing read only files.

I just installed an new computor, running XP. I had a
large number of graphics on my old Win 95 system. They
were copied onto a zip disc, dumped onto a memory stick and
then uploaded onto the new system. Now all of the files
come up as read only and I can't do any changes, add or
subtract from them. How do I work around this. I've tried
to change the files & folders attribute from read only, but
it doesn't take.

Thanks in advance
Matthew