Although i regularly clean the registry,delete temporary files,empty recycle bin,run adaware and avg,and defrag my PC it is now taking several minutes to boot up. I would like to make sure that there are not items starting up that I may not need but not sure how to check this. Also does it matter how many icons are on the desktop as I am always adding them. most grateful for any tips.
many thanks.

It does matter how many icons are on your desktop and lots can slow down the boot process. But once the boot is complete, and all the icon images have been read in and displayed (which takes some time) then speed should not be a factor, though you may notice when Windows refreshes the desktop.

What I do is have a folder on my desktop called "Stuff" and I just put all but a few of the basic shortcuts in there. If I find it is a shortcut I use often, I add it to my Links toolbar, which contains 8 folders.

Also note that cleaners and scanners frequently mark files for delete at next boot and this can slow down the boot process too. My machine takes about 4 1/2 minutes until the last icon pops into my System Tray.

thanks for the info-very helpful.