Here's a decision tree that may help you figure out what is best for you.
If you feel that you ought to pay the debt on ethical grounds, then we're done. You have to pay it off. Otherwise you'll never get any sleep.
If you don't feel that way, then you should assess how burdensome paying the collections would be. For example, maybe the dollar value of the collection is so small that paying the full amount would be peanuts for you. If so, then pay it off.
If the amount involved would be at least somewhat of a burden, then you need to ask whether there are any important credit needs that could arise before the collections would all drop off. You mention that you might buy a house in a year, which is before when the last of the collections will fall off.
If the advantage to ignoring the debt is greater than buying the home soon, then do not pay the debt.
If you are certain you want to buy the home sooner, then pay the debt off.
If you are not certain when the home purchase might fall, you should delay paying it off in the hope that the home purchase will occur after the collections fall off.
A few final thoughts. You write: ".... should I call and pay in full and have the collection agencies remove from my credit report?"
That's the wrong order. Do not pay and then expect after that that the CA's will remove. Negotiate an agreement of "Pay for Delete" with the CAs first. Talk to the folks in the Rebuilding forum on how to do it. No CA has to agree to this.
Look into what the Statute of Limitations is for your debt. It's theoretically possible (depending on where one lives) that the debt could fall off your report before the SOL expires. You want the SOL to have expired before you do anything: whether negotiating with CAs, buying a house, etc. Bear in mind that you will always owe that debt. When it falls off your report, it means simply that it has fallen off your report -- not that you don't owe it. And when the SOL expires, it doesn't mean that you don't owe that debt -- it just means that if someone were to sue you in court for the debt then you could simply observe to the judge that the SOL had expired and you would be guaranteed to win (assuming you showed up to court).
