Well, you first need to resize your English graphic and make it use three colors like the original Famicom graphic.
And... I think you realize it already, but the title screen's different pieces (tiles) are scattered in the ROM (you can see it in the PPU Viewer window of the FCEUX emulator) like you found out.
which means you'll need to either:
a/ insert the new title respecting the original arrangement (so, you'd use Crystaltile2's tile composition tool and reconstruct the title like seen in-game, export, modify that image in paint or whatever than reinsert it).
b/ modify the arrangement of the tiles (what we call the "tile map") to better suit your new title.
Emulators like FCEUX (Name Table Viewer) or NO$SNS for Super Famicom (VRAM Viewer) among others... offer tools to see what this arrangement is like.
One easy way to find the tile map for NES games would be to make a second ROM where you replace the part appearing in the PPU from the graphics with an image like this, where each tile has its index written inside.
You get results a lot like this:
(You're not supposed to insert ALL of the "guide image" tiles, you may just put the ones for the first few lines and leave the rest alone if that's where your title screen graphics are. The reason why the whole screen looks liek that is that the "blank" tile repeated for the empty parts of the screen was also replaced by a numbered tile)
Now using a hex editor you can search for the tilemap data for that orange part of the menu, looking like "20 21 22 23 24 ..." (without spaces) in the hex data.
Note that there are cases where this doesn't work (notably sprites).
And, for SNES games, it gets a bit more complicated and tile indexes are followed by more info (if they are mirrored, etc) and I'm still a noob regarding SNES and GBA/DS tiles even though it could save my life for something I'm needing to get done right now.