no budget, whatever's best.
plans?
I am not up to speed on your interests...are you? The hobby has many 'flavours', and it is almost always a good thing to spend some time up front trying to narrow down your approach to the hobby. For example:
What era? Pre-WW I, Depression, War, Post War, Modern? The hardware varies with each era. So would the look. Many railroads that existed 60 years ago no longer exist. We call them Fallen Flags. New York Central, Missouri Pacific, Pennsylvania Railroad, Norfolk & Western, Santa Fe, Great Northern...you get the idea.
If this really is, and ought to be, simple, and you just want something with a motor that looks pretty, then for diesel, among the best looking are the Genesis brand. The best drives are from Kato, and they also look pretty good. Atlas has a sterling reputation. I love my Fairbanks Morse Trainmaster H24-66 with QSI decoder in it.
For steam, it is hard to beat Broadway Limited Imports. The best detailed engines I have, though, and they are completely reliable, are the Rivarossi Allegheny 2-6-6-6 and my little Proto 2000 Heritage Series switcher, the 0-6-0.
For value, still with steam, it is sometimes hard to beat the Spectrum series from Bachmann. Their wonderful 2-8-0 Consolidations are gems. I hear their Heavy Mountain with its all metal construction is also a gem, but they are rare.