This blog takes a look at how it's been to use Ubuntu for quite some time.
Read it here
So far I havent run into much I cant do with Ubuntu:
I have a few old applications which use an Access db (I know!) and those I cant open and have to use a Windows PC
I had previously used Microsoft Publisher to do our Xmas newsletter and I had to open that on my wifes PC and export it to text – which I then copied over and redid it with Open Office.