Starting off I went through some old photos I took in 2005 on a trip through Rocky Mountain National Park just outside of Grand Lake, Co.
Notice on the top you can see the edge of the worn photo. After a quick crop you can no longer tell it was a printed photo and can now be uploaded or backed up.
The first time I scanned, I adjusted the quality on my HP Photosmart C4750 3 in 1 printer a little too high, well actually all the way up to 4800dpi and I think it ended up being 1.5Gb(and about 1/2 an hour). It's kinda useless to have a photo so large since most sites won't allow it(WordPress allows up to 1Gb which I'm sure helps to encourage buying more space).
These settings were a little more reasonable without being all the way at the lowest quality. Here's some photos showing the steps needed to change the quality of your scans using the printer I mentioned above.
Click > Scan Picture.
Picture to File should already be selected. Click > Change Settings.
Click > Advanced Picture Settings
I adjusted the resolution to 600. I made sure Sharpen and Remove Dust & Scratches were checked, then checked the box under Quality vs. Speed. Click > OK.
I changed the Base File Name(you can rename later but it will be easier to find if you change now). The bottom box will show where the photo will be saved(you can click > Browse... to choose another folder). Finally click > OK then follow the normal steps to complete your scan.