corsair 450VX or 520HX will take care of everything. be aware, the 8800GT is a single slot card, so you will need proper case cooling, or else the card will overheat.
that 8800GT will do; it has the dual slot cooler, which is better than the single slot. NEVER go with a el-cheapo power supply. stick with antec, corsair, seasonic, thermaltake, pc power&cooling. if you get a cheap power supply, you will damage your system.
that'll work. they are said to be reliable. practically all members would recommend a corsair unit because they are solid and stable. may be on the pricey side, but it's worth it.
all psu fans are pointed inside the case. if you place the psu with the fan on the top, you won't be able to screw in the psu, since the screw holes won't line up.
