I don't really understand your question as you mention something "near Bangkok/Pattaya", but then go on to talk about Samui. The nearest beach destination to Bangkok would be Pattaya. Samui is much further south on the opposite side and you would need to take a flight to get there, whereas Pattaya is less than 2 hours by Bangkok in a car. Hua Hin would be another destination worth considering.
Read up on Koh Samet which is beyond Pattaya. It is reachable by bus/minivan + short ferry crossing.
Depends what you are looking to see and do whether you want lazy beach time or you want more activities, there are lots of choices
Monica4: Thanks for reply. Am travelling with my wife along with an infant and a 5 yr old kid..so need to relax only in a good resort. Not keen for too much of activities.
@Cassnu: Thanks for the suggestion. Didn't know about any famous beach destination "near" pattaya..! Anyways, If i consider Hua Hin..can u suggest some good beach properties providing ocean view rooms..?
What is your budget ?
Plenty of luxury places in both Pattaya and Hua Hin , Intercontinetal in Hua Hin has great sea view rooms excellent service, but it all depends on your budget , in Pattaya the luxury Centara Grand Mirage Resort has amazing waterpark style pools swimways and great sea view rooms and lots of family facilities, the Dusit Pattaya also is very nice
Pattaya is way more busier though than Hua Hin
I would say Hua Hin would be best and easiest to get to with young kids. Maybe Ko Samet would also fit the bill.