Slow download of front screen and desktop

Hello,

Hi there my computer seems to take for ever to dowload desktop icons once the boot up is completed. I've have resorted to only four icons on the desktop but it still takes for ever. I have also disabled my virus/spyware to see if this is problem and looked up at start-up but cannot see anything obvious that could cause this.

Any ideas please....I do a regular maintenance and I still have 85% free space.....to work with.

Thanks guys