Frozen food cooking query?

Hi I left some food at a friends place, while had to immediately seek emergency accommodation.

now I'm in emergency accommodation and the only cooking facilities I have access to is a small microwave and a toaster.

I thought me mate would of had the decency to see what was frozen at the time and what was not, and placed them in the fridge or freezer, instead of just chucking everything in the freezer.

Q1:The food i have is Steggles frozen crumbed chicken fingers which is supposed to be cooked in a oven or under the grill, (just wondering if they can be cooked in microwave, and for how long, and if so would they be better defrosted thirst or nuke them frozen)?

Q2: The second is a large tube of potato salad which was fresh until my mate put them in the freezer, (just wondering if it would be still okay to eat, once defrosted)?

Q3: I also have some frozen fish fillets, but once again they have to be cooked in oven, grill or frying pan, (will they be okay to cooked in microwave)?

So would this stuff be okay to cook in microwave and eat?