I think you're super smart to start so early! I scanned photos to put in an album for my son two years ago and it ended up taking a long time. I ended up staying up til the wee hours every day until Christmas!
I went through snapfish.com (it was the only photo site I could use at the time, I think because of some Windows Vista incompatability on my computer). It's nice that you can upload photos that stay on their site, just in case your computer crashes. You can pre-purchase a set number of prints to mail-order and just click on the prints/sizes you want when you're ready.
I ended up having them sent to a local Walgreen's so I could pick them up the same day, which cost a little more than the pre-purchased mailed prints but it was nice to have the cheaper option if you allow enough time.
It's a big job but it's a nice trip down memory lane. Have fun!