What a great machine! And welcome to the Board!
First, make sure you do NOT use water or anything water based to clean the machine, the decals will be wrecked in a hurry. Use only sewing machine oil, real sewing machine oil, with cotton balls or something similar. If it was me, before completely disassembling, I would remove the easy things, plates, cover, motor, hand wheel, then oil (with sewing machine oil) all the oil holes and anywhere else metal moves against metal. Let it sit for a while, see if the machine moves, if not then repeat. Once it's moving you can "wash out" rust from machined surfaces with sewing machine oil by continuing the process.
If you're comfortable taking it apart completely, then proceed. I've seen videos of people doing that, and although I know I could take one apart, getting it back together correctly would be a big concern.
You're on your own with what to do with the green table. If you like woodwork then it's a great project for stripping and refinishing, if not...I would pick a paint color I like!