ThumbsPlus does the job for me. You may find it well worth the purchase price... or you may find a crack for it.
Do a batch process and select an input folder/file/selection and transform them all to 50% horizontal and 50% vertical (or whatever % you need) and you are on your way. It also has a thumbnail HTML page generator which lets you click on the thumbnail to bring them up full size.
Any more questions, feel free to ask... I've actually got picture pages on the net using the software.
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12 gig empeg Mark II, SN: 080000101
30 gig RioCar SN: 30103114
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