A while back when my husband and kids were off camping, I spent most of a rare weekend alone tackling a big project - several large Rubbermaid tubs worth of old photos, getting them organized to scan.
Normally, I would advise someone to tackle a project like this in stages, but I know myself and my schedule and I also know that with a tedious job like this, my best bet is to do it in one large chunk because otherwise I can let a project like this drag out for weeks, or months, or years...
It does help to know yourself and your work style and know what is a realistic way to tackle a large project like this.
In my house, photos and other personal mementos are probably my largest source of clutter. I'm pretty sentimental and we have lost pretty much all of our older relatives - grandparents, all four parents, and most of our aunts & uncles, so these items are the only things I have to remember them by, so they are precious to me.
But it is a LOT of stuff and it takes up a fair amount of space in my house. However, since it does have a lot of it has meaning to me, I am willing to forgo other types of clutter to make room for it. I keep it all in a large cedar chest and three large Rubbermaid tubs that fit neatly into the closets in several rooms. So, even though it is technically clutter, it is fairly neat and pretty organized clutter.
So, it's a big, ugly job, but I'm definitely off to a good start. First I got all of our oldest pictures out of those old-style magnetic albums that were ruining them. That was a heck of a job right there, I'll tell you!
I've also gotten all the old pictures out of their individual envelopes and gotten them all sorted by size which is required for scanning.
And I've weeded out all the negatives and thrown away all the paper envelopes that were taking up a lot of room. Yes, I hear you gasp, but I know perfectly well that I'd never go back and go to all the trouble of figuring out negatives to get reprints of anything made from them. And besides, the last thing I need is MORE pictures, so I felt comfortable in decluttering them.
Duplicates too! Lord in heaven, who ever came up with that particular marketing scheme? I had 4 or 5 copies of some pictures - ugh. And don't get me started on all those little wallet sized school pictures we'd amassed over 25 years of school pictures.
Sorting the pictures is a big job too. Do you sort by event, by date, or by who is in the picture? I went for the latter option. You can get totally crazy with that, so I settled on a few basic categories - immediate family, extended family and friends, pets, and pictures of "stuff". My husband loves to take pictures of "stuff" - animals at the zoo, fancy cars at car shows, sunsets, flowers, you name it. My policy is that if it doesn't have a picture of my kids in it, I ain't too interested! And I even pitched a few blurry shots and the ones with people's heads cut off.
So the basic strategy is this - determine your priorities, get the clutter down to the bare minimum you can live with, store it in a way that the items are protected from dust and damage, organize them in a way that makes sense to you, and then come up with a way to actually get some use out of the items, such as scanning them into a computer for reprinting or scrapbooking. Make sense?