I don't know if any of these will help but...
A couple more at kellys-korner
121. Increase Icon Cache
166. Add Icon Cache Size to Folder Options/View (on the right side)
I've used this one to increase my icon cache size without having to fool with the registry. It's possible your icon cache is too small. After running it, you will find about 4 different size settings at the bottom of the list of settings in the view tab.
(I've used this one in the past also.)http://camtech2000.net/Pages/Useful.html
You may have noticed that sometimes the Desktop and Windows Explorer start to display the wrong Icons for some file types. Running RefreshEm when they do repairs the Windows Icon Cache so that the proper ones are immediately displayed. It does not stay in memory, immediately terminates after using it and has no visible Window. Just click or double click the Icon each time you want to refresh the icons. Win95/98/Me/Win2K/XP
Download 79 Kbhttp://camtech2000.net/Programs/refrsh10.zip