or better still goto ping.eu select ping it tells u amount of data sent and received that'll tell u if the ip is working or not.
Now talking of proxy software there are many out there lyk charron,proxy switcher and the rest of them but the very best remains proxyway. This software is so cool that it download proxies and automatically test them and it gives working one only it tells u the location anonimity protocol respond time of the proxies in the tabular form.
U may also find proxy finder and proxy checker usefull. One finds different proxy and the other check out for working ones only.
Enjoy Guys! and your feedback on this topic are very much welcome...