There are times I would like to just cut and paste material from Wikipeda to my site. Can I do this legally.
Yup! It's perfectly legal, and good form also requires that you cite your source. So long as you say where the information is coming from (Wikipedia), then there's nothing stopping you from using that on your own personal website (so long as you are not making a profit from that information in any way).
like animal said yes, you can even putz content direct from wikipedia on your site or on your software , i've seen babylon doing and asked in wikipedia and they tell its allright...