if you plan to go with a group of people, go to the blue elephant in fulham/chelsea (www.blueelephant.com) - great food, great service and a great setting!
or if you fancy something a bit more romantic, go for the sugar hut - also in fulham/chelsea on north end road (www.sugarhutfulham.com) - again, great everything (except the drinks are a bit pricey)
otherwise, have a look at www.toptable.co.uk for a wide range of other restaurants.
thanks! the blueelephant sounds great! I love great Thai food (good value for money)...not too expensive! For about 4 people and in putney area so that perfect! Any more suggestions very welcome!