First time visiting the USA and Boston, can anyone give me any advice on good restaurants & bars to visit? What would you recommend as regards to sight seeing tours and those to avoid. Any info would be very much appreciated.

Doyle:

Try the duck tours while you are in town.
http://www.bostonducktours.com/

They go by my house here in Charlestown and they look like a lot of fun.

Olive's is a good restaurant here in Charlestown.

Spire @ Nine Zero is also very good (the chef calls the food Romance food)

Also try out the Freedom Trail, it is a good walk that goes by most of the sites here in town.

Finally, if you are looking for a place to stay check out
http://www.hotelchatter.com.

I am the publisher of the site and we have quite a few Boston hotels. One might fit your style/budget.

Cheers,

mj