To summarise...
Architecture Wizard:
A quick point and click way to generate HDL for the DCMs and RocketIOs
Chip Viewer:
A version of FPGA Editor for CPLDs
Constraints Editor:
A helper for writing your UCF files
Core Generator:
A wizard interface for Xilinx (and 3rd party) IP
Floorplanner:
A tool that lets you assign HDL modules to specific areas of the FPGA
FPGA Editor:
A viewer/editor of the FPGA resources that are available and what has been used and how the nets are connected
iMPACT:
Configuration/programming tool (mostly for JTAG, but does other related stuff)
PACE:
Assign package pins with a drag/drop interface (also handy for viewing FPGA pinouts)
StateCAD:
A GUI state machine creator - outputs HDL
Timing Analyzer:
Static timing analysis tool
Webupdate:
Software updating via the Internet
XInfo System Checker:
Use this to get your system info if you're reporting a software bug
XPower:
Power analysis tool