hi Haru,
I liked Grand Diamond which is opp Pratunam area. It isn't the closest hotel to any train station (prob 5-7 min walk to the train station where Asia Hotel is), but the cool thing is tt it's located along a main road & it's an all-suite hotel. I loved it's room, nothing outdated at all, the living room & bed room are seperated by a door & huge TV console
U can actually do simple cooking in the suite too, in the event u just happen not to be able to go out or sthg
I've also tried Windsor Suites near Emporium. Also an all-suite hotel, but the rooms are a tad older but the whole ambience of the lobby & cafe is pretty gd. The staff who help at the lift lobby are really gd, very polite & wld assist. Not the most convenient location to a BTS either, at most 5min walk.
Pathuwan Princess & Novotel are hotels which many S'poreans wld select, being the nearest to MBK & the train station. But more pricey..
Others like to try Baiyoke Sky where the rooms give u a gd view of BKK city & it's located within Pratunam
U might want to surf Asiarooms.com for more info on the hotels u have short-listed & assess before deciding which hotel to take-up
My first trip to BKK I went to Wingo travel at Ppl's Park B1, my 2nd trip i booked thru Asiarooms & flew by budget