The softkeys can be changed by selecting a different theme in the Today Settings.
As far as the full wallpaper, it's tricky and not perfect on 2.5.1922 builds so far. I have had pretty good success, using a transparent softkey theme, along with MaxTTM to make the wallpaper full screen. It does not work on all roms and will not look right without having a trans softkey theme.
Having said all that, MaxTTM also will not work with the Landscape B4all mod that's available, same with this landscape B4all 16 links mod.
I have gotten MaxTTM to work with the B4all landscape, but not perfectly. As you will notice in the pictures, it's not real a clean transition from wallpaper to the bars. The only way this will work at all with the landscape mod, is to select the same wallpaper for both Portrait and Landscape 4 all tabs. Then do the MaxTTM convert process that I have explained in a couple of my other threads. If you don't know how, or can't find it and wanna try it out. Let me know. I'll point you to my small walkthrough to setting fullscreen with MaxTTM. You would still need the Trans Softkey.tsk that I am using.
If you are interested, let me know and I'll see if I can dig up the .tsk and guide for you.
It also leaves a black line with the B4all landscape mod, when using MaxTTM, as shown here:
