Heyyo,
copy anything important from your metamod.ini, then rename it to something like "metamod.ini.bak" as a backup, and then just use your plugins.ini... NEVER attempt to use both. If you set up metamod the default way, it should be in "addons\metamod\dlls\metamod.dll"
now, your plugins.ini should be in "addons\metamod\plugins.ini"
and then make sure you properly route where those dll files are from where the metamod folder is. use "..\" to make it go back 1 folder. So 2 inna row (..\..\) will go back 2 folders back to the main folder of that mod.