Gerry, as Paul said earlier, try not to use your operating system hard disk as your Primary Hard Disk for Photoshop/Bridge, and don’t forget you can set multiple drives as scratch disks..at least in CS4…and I think in CS3 too. If you have fast external Firewire drives, count them in too.
Hi Janine, as the previous person said, maybe easier to go back and reshoot if possible, otherwise what I would try is…..
Make a very loose selection around the foggy area with the Lasso tool
Feather it quite a bit, or hit Q for Quickmask after you have made your selection as above
You will see a red mask…..now Filter>Blur>Gaussian Blur to visually feather the selection and get a nice soft mask
Hit “Q” again to exit Quickmask
Press Command/Ctrl H to hide (not drop) the selection
Try a small levels adjustment to add back some contrast to the foggy area, trying to match visually the rest of the pic
Try a little Unsharp Mask