If Electrum would ever be discontinued in the future and all the servers went offline, could you then still use it to send money by downloading the block chain on your own computer?
If you want to do that, you'll need to run your own server.
Or do you then need to export the private key and import it into another client?
You can always export your private keys even if all servers disappear. Your private keys are generated on your local computer.
And suppose I lose wallet.dat do I get everything back when I import the seed and can I then recover the private key?
If you restore from seed you'll get your transactions. Labels and contacts are located in your electrum.dat, you can use a plugin like
LabEletrum to keep a copy out of you deadly PC.
I ask this because I am thinking of using an offline Electrum wallet for saving some coins in. And maybe not access them until years later.
Good. If Electrum ever disappear you'll be able to export your private keys and import them to any other client.
