I am doing my own invitations on my home computer. Is it ok to print the address on the envelopes using my computer or should I hand write them?

Invitations should be addressed by hand. While this certainly takes longer than computer generated addresses, it is the correct etiquette thing to do. If you don't want to or have the time to address them yourself, you could print a list of how they should be addressed and give that to a calligrapher or someone with neat handwriting. Or see: Import People

That said, it is becoming more common for couples to use computer labels to address invitations. While I do not agree with this practice for wedding invitations, I do see it happening more often.