can anyone please advise my targa make a loud banging noise over everthing the top sits flush with the whole body. but over every bump it makes a rumble noise or bang please help !!

Two things probably causing this.

1) You need to have the roof clamping mechanisms tightened. There was a Honda service bulletin about tightening the roof. Costs some cash but should fix it. Go to the dealership and have it done right.

2) Try lubing the weather seals around the roof and car where the roof touches. May just need a good lube - mine squeaks and rattles a little as well when the seals need to be lubed. Lube the locking pins on the roof as well. Get a tube of lithium grease from Honda and use that and a can of silicone spray from Honda and use the spray on the areas where the windows touch (and allow it to dry). That way the window areas won't smear. The instructions below should help and it has the lithium grease Honda part number as well. Tube should cost you about $15 give or take and the spray will run around $6 or so.

Instructions on how to lube the targa seals (http://www.teamdelsol.com/technical/howto/lubeSeals/default.asp)