Ok I'm going to answer a lot of questions here.
@ghost recon 88 GUIminer is your best bet. I use it on one machine. It is a front end interface that has several different miners available. I would suggest running a phoenix miner for the 5870 and a poclbm miner for the 6950.
@chihlidog and Aikouka There will be variances between blocks. One may take 4 hours. The next may take 4 minutes. It is even over time. (I remember one block Slush pool found in 1 second, I didn't even get any shares!)
@ImDonly1 Estimated means your estimated return for the current block. Confirmed is all of your returns that have been confirmed by the network, unconfirmed are the more recent ones that have not yet been confirmed. Also, always running the client when you have a pool isn't required, but the wallet HAS to be open when the pool sends you BTC. That's why I would just leave it open. Once the initial block chain is downloaded, it uses hardly any resources at all, so it shouldn't be a problem.
@Drivenbyvoltage I would not suggest setting the threshold to 5+. Most people won't even get that in a week. Especially not after the impending difficulty increase (sometime tomorrow). This is also bad because if your pool holds all of your BTC, if you need to sell quickly your are screwed. The best place for your BTC is your own personal wallet on your computer. We have our send threshold set to 2, but we get that fairly quickly because we are netting ~1.2 per day.
Also, how about that projected increase? 50% eh...