Even the XP version of Windows makes a difference between 32-bit and 64-bit and this seem to be the 32-bit version. If you would have the 64-Bit version it would be stated otherwise.
Basically all verisons sold in the usual shops or bundled with PCs are 32-Bit. On the otherhand even if you would have a 64-Bit Windows installed it would not be pretty usefull since technically 64-Bit is just used in order to have the abillity to use more
RAM than 3 GB, and you only have 2GB. But 64-Bit Systems are also capable of running 32-Bit programms.
Downloading the 32-Bit Version is definetly the right one for you, since you have a 32-Bit Windows XP.
[Edit]: Next time you can do a screenshot with the "print" key on your keybord, then open for example GIMP or paint, paste it their and your faster and easier done :)
Instructions re the "32-bit" or "64-bit" version of Image Composite Editor
