Hi,
We can not fill-out an infopath form, if we not infopath installed on our machines,
There is tool "InfoPathDev Forms Viewer", which supports to view the infopath forms on browser in infopath not installed systems,
For more information check this link,
http://infopathdev.com/webstore/detail.aspx?itemid=11 and this feature is added in next release of infopath.
Thanks.
K.Ramana Reddy / http://www.ggktech.comIndia.