Alright, I checked the .NET 2.0 redistributable, and while it lists /Q for quiet install, it ignores the switch. You could use the psexec -i option, but that kinda defeats the purpose of remote installing, as it would require user intervention.
Your other option would be to unpack the .EXE, and go directly to the .MSI. To unpack, use:
dotnetfx /t:c:\dotnetfxUnpacked /c
Then you can use psexec to run C:\Windows\System32\msiexec.exe c:\dotnetfxUnpacked\netfx.msi /quiet /log c:\dotNetLog.txt
I'm still not sure if that'll work, or if the .MSI requires some information the install.exe provides. I doubt I'll find out, as I'm running in 64-bit, and I downloaded the x86 package.