Hi. I have worked in West London for years. West london is really a mix of things, so it depends on what you are looking for and what "good" means to you.
Ealing and Ealing Common are lovely, leafy and quite middle class as is Chiswick and parts of Isleworth. However, Ealing and Chiswick are very expensive, but have great shopping, restaurants and night life. Isleworth is not as expensive, but doesn't have as good of transport links or all of the amenities.
If you are looking more for multi-ethnic environments--Hounslow is very diverse and has decent transport links. It is not as expensive. Shepards Bush and Acton are also very diverse and have decent amenities, but as was mentioned above, have had problems with crime in the past, but loads of work is going on to stop it. Southall is an amazing place--a different world. Very diverse with loads of Punjabi shops and restaurants and is very lively.
If you happen to be a neo-nazi or white supremacist, then feltham could be the place for you as it has a burgeoning BNP party. However, it is undergoing massive redevelopment in its town centre and is the focus of work to develop better relationships between the disenfranchised white communities and other ethnic groups. Housing isn't expensive and the transport links are good because of its proximity to Heathrow.
South West London is great as well--I have lived in Richmond and Putney and love Kew and Kingston. It wouldn't be too hard to get to ealing from Richmond, but it is expensive.
You could also look further west outside of London-- various trains to the west stop in Ealing Broadway. We are moving to Windsor and Ealing is about 15 minutes away by train.
Good Luck