Here we go! Be prepared to be warned about manual dexterity, failing eyesight, terrible performance and bulky details... N scale, afterall was spawned by Satan himself...
Of course I jest. Lately these discussions have been very helpful and even civil! I just thought I'd get that out of the way!
Anyway, what would really be helpful would be a sketch of the area you're working in, not just the size of the table top. It sounds like what you have is an L shaped space that's roughly 12' x 8'?
The main advantage you'll find with N scale is that you don't need your table to be a full 4' wide. That makes it very difficult to reach the back, and in the corner of your L, you won't be able to reach that at all, unless you pull it away from the wall to be able to walk behind it.
N-Scale will give you more possibilities in your given space, as you can reduce the table width to 36", and still have a reasonable main line run, and plenty of room for scenery and structures. To give you an idea, the area in the photo below occupies about the space that you describe...
Never mind the debris!
Now there are lines that extend around the room to support things like a yard and some staging, but the basic layout can stand alone, if need be. Here's the track plan:
To dip your toes into N scale, I recommend you invest a little into an Atlas Trainman train set, which includes a very good quality locomotive, a basic power pack and some track to get you started.
Rather than begin by planning out the whole space, start with a small, simple plan that uses the set track, and maybe go buy a couple of turnouts and some flex track to experiment with.
Then build out your small "test bed" layout with some scenery, structures, vehicles and trees, and see how you like working in N scale. You'll end up spending about $200, so if it turns out you prefer HO, you're not out a whole lot. Package the set back up, and you can probably sell it on ebay and get most of your money back to start over in HO.
If you like the way N scale looks and handles, then you have a good start underway, and you can start thinking about upgrading to a more scale looking track, adding to your fleet of rolling stock, and maybe picking up a few more locomotives.
At that point, we can go more in depth about planning your full layout. There are some very thoughtful folks here on the forum (and elsewhere) who can help you through that process once the scale issue is settled.