Mini ITX build

[Lucasaee]

Hello,

I'm building a Mini ITX media center using a MSI H61I-E35 Motherboard.
It has:

4GB Kingston HyperX DDR3 RAM
Intel G530 Dual Core (2.4Ghz)
Lite-on iHas DVD burner
No hard drive but looking for a 1TB HDD (full size, cheaper)

I have a few questions:
1. Will a 300W PSU, Mini ATX, Unbranded be OK ?
2. Can I add a PCI-E LAPTOP wifi card or does it need to be compatible with the board ?
3. Can I add USB 3.0 via pinouts on the board, I want to replace the standard USB's on the front.

Motherboard image & details here:
http://www.amazon.co.uk/MSI-H61I-E35.../dp/B004UBCMU6

Cheers !

[eBombzor]

1. Depends on where you get it. Check the OEM
2. Most laptop wifi cards are mSATA. mSATA is basically a SATA connection wired to PCI-e. Not sure if it'll work.
3. Not sure.