4Gig Patch which is in the SH3 section, but works as well with SH4, or any older 32-bit app that it written in 64-bit flat addressing and does NOT have the header bits already set.
Large Address Aware (LAA), which might require downloading some NetFramework files on your computer.
Both applets serve the same function, and that is to flip a couple of bits in the header of the executable that lets Windows know that the app (SH4.exe in this case) can address more RAM without the use of an offset. You want to make certain that SH4.exe is write-enabled for one of these to take. So find the SH4.exe file in your install folder, right-click on it, and choose "Properties" from the bottom of the resultant context menu. That will bring up a little dialog, and the setting you want will be on the "General" tab. At that bottom of that page is an "Attributes" section, and a "Read-only" tick box. Make certain that box is cleared, and the file is then "write-enabled". The patch files should then function as intended.
That same "Properties" window is where you can set the video stuff on the "Compatibility" tab, as Kal_Maximus_U669 points out in about the middle of his pictures posting above...