sometimes a damp cloth works wonders with a good polish afterwards - give it a gentle buff while it dries. Otherwise there are cleaning wipes available specially for LCD monitors.
Pretty much any old non-abrasive cleaner will do. I use Carrefour General Purpose Cleaning Spray (do you have Carrefour in England?). I definitely wouldn't use a specialist computer cleaning product - they're just the same stuff at 5 times the regular price.