Is this cpu good enough?

I would get a 955 and OC it. Also I wouldn't get that mobo mostly because I'm partial to elitegroup. Do you have ddr3 memory as ddr2 will not work with new am3 boards. What is your budget and how flexible is it? To answer your second question in terms of gaming performance AMD and Intel CPU's perform similarly with the exception of multicard configurations where intel wins.

i got 2GB DDR3 1600 kingmax
and i really want some suggestion for an intel core i5 and a suitable motherboard
because i might cancel the AMD

Intel wise go with the i5 750 and this mobo

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Why? Same performance, lesser cost.

Really though these guys are right about going AMD.
I just gave Intel suggestion cuz you asked.

Like enzo said, with only a GTX 260 you'll gain nothing with a faster CPU.

There is a substantial performance gap between the i5-750 and the Phenom II 945, but both CPUs are so strong that you won't be able to tell the difference in gaming without some serious GPU power (except maybe in CPU dependent games). This is due to graphics cards being the main factor in gaming performance. The CPU only has to be fast enough to keep up with the calculations.

You could go as low as an Athlon IIx3 440 if you wanted.