1. No different than XP. Same workarounds for old games that won't run.
2. There's a classic theme (95/98 style).
3. Go x64 (64 bit). Every new installation of windows now days should be x64. x86 (32 bit) is on the verge death and you will end up re-installing windows shortly if you go x86. x86 (32 bit) Won't recognize more than 4 gigs of memory, keeping in mind that your video card shares this memory space. ie. 1GB video card, 4GB Ram, OS will only see 3GB of RAM, 2GB video card, 4GB RAM, OS will only see 2GB RAM. It's got to do with the maximum number that a 32 bit architecture can recognize vs 64 bit. Basically, the largest integer that a x86 OS/architecture can recognize is 4,294,967,296 (4GB) and 64 bit 18,446,744,073,709,551,615(????). So x64 has some future proofing =)
4. XP and Windows 7 network perfectly fine with each other. The network at my office was running like this for a while as people transitioned to Windows 7.
