at 6 and a half months he can have finger foods, basically whatever you are eating (minus salt!) my preference is to cook fresh, if i was cooking for everyone else it's no bother to do a bit extra for the baby. but if you want to do things in advance you can keep it for a couple of days in the fridge
I froze mine, and defrosted in the microwave as I needed to use it. You could keep it in the fridge for a day or two, but freezing it in ice cube trays (or poncy Annabel Karmel weaning trays if you're like me) is much easier and avoids wasted leftovers.
Get yourself a couple of these: http://www.amazon.co.uk/ZEAL-J251-SILICONE-BABYFOOD-TRAY/dp/B00309H9CK/ref=pd_sim_kh_1 - far easier than any of the pots or trays I tried with ds1. Freeze the tray and pop the cubes out into a labelled freezer bag the next day. Annabel Karmel reckons that foods last for 8 weeks but I've read elsewhere that 3 months is fine and I'm sticking to that! Dd2 is now 10.5mo and eats 2 cubes of savoury and 2 cubes of fruit for dinner. Dd2's favourites and easy things to make include:
Roasted sweet potato with some cheese grated in Red lentils and spicy root veg (carrots, parsnips) Red lentils with fried onion and coconut milk Shepherd's pie - also made a mildly spicy version with Morrocan spices Bolognese Carrot, tomato (blanched to remove skins and deseeded), and onion Broccoli, cauliflower cheese Broccoli and carrot with a little cheese sauce - used as a pasta sauce with tiny pasta shapes or penne to hold and chew
Easy fruits to puree which don't need cooking and can be mixed:
Peach Mango Strawberries Raspberries Blueberries (skins are indigestible so come out in their poo!)
Hope that helps! It's satisfying to watch them eat things you have (lovingly!) made.