Glossy vs Matte: Glossy looks really nice but it can cause a lot of reflections. If you are going to use the laptop in a lot of brightly lit areas, I'd recommend you look at the matte. Otherwise, glossy will do. I got a glossy LCD for my office and left my laptop as a matte.
I can't stand the "Mighty Mouse". Test it out before spending the cash. Apple does a lot of things right, but it cannot figure out how to design a proper mouse. Any Logitech or Microsoft mouse will work as both manufacturers have released OS X configuration software. I prefer MS mice, but it's up to you.
If you're tight on cash, get the Linksys router. The Dlink is decent but if you want to more stuff (network backups, lots of throughput traffic), you'll end up replacing it. The Airport might be more then you need but it's definitely a good product. I'll probably replace my D-Link with an Airport Extreme just for the network hard-drive features so it can interface with Time Machine.
When I upgraded my Macbook's memory, I bought a 2Gb single stick from Memory Express and replaced one side. I now have 2.5 Gb of Ram in my Laptop and it's purring along very happily. Haven't felt a need to get anymore since my free RAM has never dropped below 1GB... As HotHotHeat said, do not buy memory from Apple. It's ~40$ cheaper if you go third-party. Just ask at Memory Express for some Apple laptop memory and they will know what you want.
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