Gardening Advice Needed, Please

We built it! Or, I should say, Greg built it, I directed, and Nick did everything he could to prevent us from getting it done.  He especially liked climbing into the beds, trying to grab Greg's screwdriver, and running away from us down the sidewalk.

 Greg and I decided that we'd like to do more in the yard this year, so the first project on our agenda was to build a raised bed system. A few weeks ago, we purchased a raised bed garden kit from Costco, and it's been sitting in our garage taunting us ever since. But Greg got all of the pieces together today, and I went over to Home Depot to get horse manure, mushroom compost, hummus, organic garden soil, and peat.

This is what the kit said our garden is supposed to look like, come summer. We shall see. We did chose a more curved setup, but we like the way it looks in the corner of our yard.

Here's how it looked with the cold weather panel and all of the soil filled in. I planted three rows of spinach seeds from the Seed Saver's Exchange, but everything else I bought says that it can't be planted until after the last risk of frost (end of May around here). My question is, since I have the cold frame, can (or should) I plant something in there now, one month early? What is safe to plant that would survive in a cold frame with a decent seal? (zucchini, beans, rosemary, cucumber) What would do well direct planted into a cold frame? Or can I transplant some of my indoor stuff that's been under the flourescent lights? Those are doing really well.

Oh, and I could also use some help identifying the plants I grew from seed. I have tomato, pepper, basil, thyme, broccoli, and I forget what else. You see, my mini-greenhouses came with these convenient little plastic things to write down what you're planting. So I used them. The first time I watered, however, all of the writing washed right off and now I'm only guessing as to what I have planted here. Any advice would be helpful. Otherwise I suppose the plants will tell me eventually. For example, if the plant makes a bell pepper, I'll have my answer. If it makes a tomato, it must be a tomato plant. Sigh. Can you tell I'm still a beginning gardener?

The plants are doing really well under the fluorescent lights, although the neighbors must wonder what I'm growing up there--the lights are so bright they light up the neighborhood. Heck, I guess I couldn't tell them what I'm growing, either. I do know that I only planted vegetables and herbs--I'll have to wait and see what kind.  :)