Optimal germination temp for many vegs, including peppers, is 86F. But peppers will germinate at lower rates from 68 to 95F. After they germinate, they like temperatures around 70F. Eggplants need it a bit warmer, maybe 90F for the highest germination rate. So if you want the fastest germination and highest germination rate, you will need a heat mat or some other source of warmth (a sunny window,* a radiator, etc.). Once the seeds have germinated, they prefer cooler temperatures (50s min., 70F best) and need light.

Lettuce will germinate optimally at 68F (range is 41-83F) and grow best between 60 and 65F. Peas also like cooler temperatures, optimal is about 80F (range is 45-90F).

The temperatures come from the charts in the catalog from Johnny's Selected Seeds.

Once the seeds have germinated, they need light! Do you have fluorescent lights?

*I've successfully germinated pepper seeds without a heat mat or lights. I moistened a paper towel, put some seeds on it and folded it over, and placed it all in a sealed and labeled plastic bag. I placed the bag in front of a south-facing window where it got direct sun for several hours. I got pretty good germination of all 6 varieties within a week or so. I then grew the seedlings in front of the sunny window.

I've also grown tomato seeds in a cold frame. They grew very slowly, because though the cold frame was warm in the daytime and usually needed to be vented to keep from overheating the seedlings, nighttime temperatures were still in the 40s.