Alright, they aren't "museum" pieces, and no one is going to be paying off their car or mortgage from the sales proceeds, but both Case and Bulldog brand knives have some value, however condition is going to seriously affect that value.
Since you want to sell them I would wipe any rusted areas with WD4 and a clean cloth, but that's it. A buyer/collector might not want you sanding the blades. After wiping the rusty spots with WD40 I would just sell them "as is" with full disclosure of their condition. Unfortunately anything less than mint condition will reduce their value, and sanding the blades, or rubbing them with steel wool isn't going to restore them to mint condition.
Also, any chemical rust removers might ruin the handles, or possibly other parts of the knives if they come into contact with the chemicals.
It's impossible to tell from that one pic what their true condition is (although some of the rust does look pretty bad). Closer pics of the knives with the blades open, and showing the rust would help determine value and/or desirability, but as I said in another thread, you would need to be a Gold member or higher for us to discuss dollar values.
What you need to do is determine the models, then you can Google them. You may find "sold" listings for the same models with the same handle materials, but again condition matters a lot.
From the writing on one box it looks like one is a Case model 5375 Stockman, and another looks like a Case 5220 1/2 Peanut,. I just did a Google search for each of those model numbers and found "sold" listings for one of each of those models. For example, search for "Case 5375 stag".
You can also search "sold" listings on ebay for the model numbers. When you do a search there click on "sold items" down on the left of the screen.
The ones with serious rust are going to take a major hit on value, possibly to the degree that they might not be worth the effort of trying to sell them.
Good luck
.