Hello. For some who don't know what Lite is Windows operating system but edited and removed some apps and services that are unused according to the user to use less resources and make pc run faster , save HDD space and other things. Here you have Windows XP Lite and Windows 7 Lite Specs.

WINDOWS XP:
# ISO SIZE = 288 MB
# INSTALLATION SIZE = 1.7 GB (with pagefile)
# RAM USAGE AT BOOT = 384 MB

WINDOWS 7 64Bit (the 32bit uses even lower resources):
# ISO SIZE = 1,66 GB
# INSTALLATION SIZE = 4 GB (without pagefile)
# RAM USAGE AT BOOT = 500 MB