Just wanted to say thank you to the people here for their help and support. Yesterday I finally managed to play the Battle for Normandy demo for the first time.
I managed to obtain an I3-4130 with 8 GB RAM, a GTX 560 ti and a monitor for under £200.
Needless to say, despite watching and reading loads about how to play, I was awful. I completed the mission to take St Martin's farm and the Crossroads but the body count was high.
Hopefully this is the start of a new hobby. I'm open to any further tips or guidance.