Recently, I got a task to install Oracle Developer Suite on Windows 7(64bit), but there seems lots of hassles to achieve this goal. There is a thread on Oracle forum on that topic. Here I log what I did to get it installed on my Windows 7(64bit) with 8G RAM.
extract the setup files (version 101202) downloaded from otn.
right click the install\setup.exe property, set compatibility to Windows XP SP2
edit the virtual memory size to custom size from 1024m to 8000m, restart it