Microsoft Frontppage is probably one of the easiest programes to use although it is not as feature filled. It comes as part of the MS Office suite so if you have Word Excel etc installed, you probably have frontpage as well. If not, you can install it of your Office CD.
Another option is Dreamweaver, but its expensive (if you buy the original version)
If you dont have either of the above mentioned software, try downloading one of the WYSIWYG editors from
Nvu seems to be the best option for you. However I myself have never used it so you may want to look at the alternatives and decide for yourself.
Also try ACE HTML freeware.acehtml.com