Go to your default data directory (%appdata%/Electrum) for windows. Copy out the folder to somewhere safe. Next, delete the folder in the appdata, assuming that you have done the previous step.
Open up Electrum and you should see this screen:
Press the options and you should see a box to fill in your seeds.
You are correct , if the OP have the seed with him then this option will open the electrum wallet and then you can send or receive as usually from this wallet, main is the seed if you have that on any system you can download the software and restore your wallet anywhere.
