Did you pick them or cut the whole plant down? What's the normal procedure?
Commercially they cut the whole plant down and run it through a machine, but picking them and leaving the plant allows all the goodness in the leaves to be returned to the rhizome, so the rhizome will be a bit stronger the next year - and that's a particularly good idea in its early years. Also, picking allows you to harvest in two lots, which works well for dry hopping a week or two after brewday, and allows you to better reflect the fact that they don't all mature at the same time. Picking is a bit of a pain, but without automation it's not much less painful picking them off a cut bine. If it's too tall, you can always cut the top part off.
The critical thing is to get them drying or in wort within hours of being picked - it's just a waste to pick them one day and brew with them the following day or later. They go "off" incredibly quickly. And remember the water content means you need about 7x more green hop than dried hop.
Also I want to do a smash with mine but as I won't know the AA I was going to use a bittering hop (I know not a true smash) so I can use my cascade as the sole hop but I only have Vienna malt. Is this OK if so what yeast would you recommend.
I wouldn't get too hung up on the SMASH thing, particularly for green hops - the whole point of green hops are the flavours that normally evaporate during the drying process, which are rather wasted if you boil them for 60 minutes! Whilst we're on the subject though,
my posts on SMASHes are worth a look.
Vienna is OK as a base malt, although personally I think you can't beat just a good quality pale malt.
Yeast - whatever you want. Assuming you want to keep it simple with dry yeast, then the obvious ones for something clean are Mangrove Jack M54 Californian, Lallemand BRY-97 and Fermentis US-05 or 34/70, and if you want something with a bit more English character then Lallemand Verdant is the obvious choice these days.