What size and type of pipe

I am almost completely gutting and remodeling my house, only thing staying is the kitchen, it's not that bad and budget issues. Anyway, I'm going to replace all of the plumbing while it's gutted, and I wanted to know what size and type of copper pipe I should be using. The pipes will be running in a 3-4' crawl space, and right now I have a deep well, with a tank in the crawl space, but I should be getting city water by next summer.
My dad, who has much more experience than me, but still not a pro, says to run 3/4" from the tank to hot water heater, and tee off of the 3/4" lines using more 3/4" to go underneath the bathrooms, kitchen, laundry, and then tee off of that with 1/2" to go to the showers, sinks, toilets, etc. Is this correct, or what should I use? Also, he has no idea about type L or M, and from a little research, K and a couple others. Anyway please help, because I want to get my water ran asap, so I can get one of my baths put in to use during remodeling.

Thanks in advance for all your help!!!

If budget/cost is an issue you might consider using PEX or CPVC.

Since you are running it in a crawl space I assume that you are in an area where freezing is not an issue.

I would go with pex. Your layout sounds good to me.

I live in southern Illinois, the winters here can get quite cold, but I plan on properly insulating the crawl space. I just don't really see any other way to go. I definitely wouldn't feel comfortable running it in the attic, and the pump tank is already in the crawl space.

And budget issues aren't that much of a concern, it's just when it comes to the kitchen cabinets, I feel that for the shape they are in they could stand to wait a couple years while I sock away some money.

Ok, i've done a little more research on PEX, and I like what i've seen. Yeah the fittings and tool is definately a downside, but I am looking at the time savings too. Seems like it would run much quicker than even cpvc. So, now I have a few new questions.

I seen that you have to use a minimum 18" "tail" going to and from the water heater. What about the other supplies? Do I run pex all the way up through the floor to the sink and toilet supply lines? What about the tub and shower? How far up do I run the pex there? I haven't seen much about the manifold blocks, but i seen something about losing some pressure with them. Would that be the best way to go, or just run it like a normal copper or cpvc line?

Thank you very much for all your help!!!

Oh and in case it helps. This is for a 1 story 2000 sq ft house. 2 full baths(including the master with seperate shower and tub, dual sink), 1 half bath, the of course normal kitchen with dishwasher, and laundry room. And am currently running on a deep well, with city water coming next spring/summer.

What PEX Brand or Type are you considering using?

Wirsbo / Uponor has probably the most expensive tool and fittings but you can size and run it like copper

Crimp type systems are less expensive for tool and fittings but fittings are reduced and although you can still run it like copper upsizing is often needed

Not sure about that part. I've only done general research. I would gladly take some recomendations on that too.

If I did new construction only I probably would use Wirsbo...
However I run into many different types being on the repair end of plumbing.
I use the Watts SSC system as it gives me the most bang for the buck and I can tie into more different types and brands with it.
http://www.watts.com/pro/divisions/potablepexplumbing/learnabout/learnabout_cinchclamp.asp

Raven Products makes the cinch tool that you can buy at many supply houses for about $50.