changing READ ONLY files attribute

Until a few days ago I have been using win98 on my system at home. I purchased a new computer that has WIN XP media centre.
All my rewriteable CD’s were ok in my old system. I could read and write to them no problem. With the new system I’m running into problems. Every time I use a rewriteable CD all the files show as READ only. I can read but I have to save as a different name. I have tried changing the attributes in the properties but they seem to revert back to read only. I have tried sharing the file and enabling full control… no luck.
If i go back to my old system WIN98 the files are ok, I can read and write.
PS> my new system has a DVD-+writer/CD-writer
Thanks for any suggestions you can pass my way