Hi Alsanad. A Warm Welcome!
On to your question: Yes the Xti does have quite a few image editing features, and the main one which your after B&W is included.
"A well-hidden, hobbyist-engaging features of this camera is the B&W filter effect. To get to it, select the Monochrome option. Now your images will be black and white".
Also, you do realise the Xti has no built in Is? or is this not a problem to you.
The Xti is quite small and light aswell. So if you like to fell your holding something or have big hands it may be a problem
Hope this all helps.