1. Which HD decided on an 11" any downsides to this? Battery is less but much better than the 30 seconds I have now
No downsides unless you need a bigger screen. I find 13" a very sweet size on a Macbook, especially the air as the footprint isnt much bigger overall.
2. processor upgrade required?
The standard CPU should service all your needs imo. With the SSD and ram, its very speedy. Have a play in the apple shop on a standard spec machine.
3. I'm thinking 256gb SSD upgrade and leaving it at 4GB ram its £80 to upgrade to 8gb
256gb should be fine. If you intend to do the ram, upgrade at build on an air. I believe its soldered on.
4. definitely need IOS and Windows 7 on the same machine what's the differenc e between parallels and boot camp
Parrallels allows you to run windows vm and apps in the Mac OS. Boot camp allows you to boot into a secondary OS. I prefer boot camp to get the full windows experience.
5. Need a soft case wich one? Any other essential point of sale required purchases
Any neoprene soft shell will be fine, but consider how you carry it. Most dont have handles on them. I have a nice samsonite memory foam case for small laptops.
6. Essential apps.
Depends what you are doing to be honest Dave.
7. I have an IPhone 5 and an IPad 4 any benefits to having all three remotes? Any hidden goodies?
You can use an iPad as an extension of the display. There are some good utilities out there to do this.
8. I have a student mate who reckons he may be able to get it cheaper, how much cheaper is it? Any warranty issues? Do I still get a VATinvoice or is it VAT free?
Student discount is much better than just getting the VAT back via Business purchase. You also get an extended Applecare warranty inclusive in the price. Dont spec this at the time of build if you are using a student "method" of purchase.
9. Windows is very big would I get away with a 128gb machine running both OS's
Id go for the larger drive if you are planning on running a lot of windows apps personally. Depends how much media you are going to bring along from the old device, and whether you store it on a NAS or external hard drives etc.
10. Apple store or eBay?
Apple store with student discount.