Hello

I'm no expert but the following should help:
http://www.awesomebackgrounds.com/powerpointgraphics.htm
http://www.pptfaq.com/FAQ00415.htm
http://www.pptfaq.com/FAQ00074.htm

Don't forget about the photo album option when you get round to making the
presentation :-) (in 2003 insert->pictue->new photo album)

Lucy

Along with what has been recommended, here is a good site for scanning
information also. http://www.scantips.com/

Read the linked pages the others have sent you, but the simple rule in your
situation is:

1) Learn the maxiumum resolution your computer projector supports.  Usually
this is 1024x768.

2) For images that will be full-slide, scan to that resolution or just a bit
above.  Or scan at considerably higher resolution (to PNG or TIFF) then use an
image editing program to downsample them to 1024x768 or whatever you've
determined your projector to be capable of.  

3) For smaller images, make them proportionally smaller.  

4) Forget dpi.  Set your scanner software to work in pixels instead.  DPI will
make your head hurt, give you bad breath and make hair grow on your palms.  Or
was that "make your palms hurt and hair fall off your head ..."?   No matter.  
It's bad.  Forget it.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ:  www.pptfaq.com
PPTools:  www.pptools.com
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