I would say important things to consider are: screen size (if you are going to use it mainly for word processing I would go for a 15.6"), processor (read some bad reviews of Intel Celeron) and make sure it has a dvd drive (so you can add new programs directly onto your laptop).
With regards to MS Office (Word, Excel, Outlook etc), you can use a free version online I think called Office 365 or something like that, or subscribe to a pay monthly version, or buy the disc yourself and upload to your laptop.
I have just replaced my laptop with one from the HP website. It has 15.6" screen, 4GB, 1TB storage and an Intel Pentium processor for Â£269 delivered. I work freelance on websites and admin and it is more than adequate for my needs.