What bothers me is the way you started your post. "With the credit crunch..." the credit crunch shouldn't be affecting your monthly budget or expenses unless you've been using credit to supplement your income. So my first tip is, pay off your loans and credit cards, the ones with the highest interest rates first. If you can, transfer any balances from the higher-rate sources to lower-rate cards. Also call your card companies to ask for a lower rate (threaten to move your balance to another account, and they will try to come down in rate to keep you). And stop using the cards. Once they're paid off, you'll have that money to save or spend on yourselves.
Bills: Stay current on them, because it will keep your credit rating good and if you ever need to be late, the creditors will be more willing to excuse it (if you let them know before you're late). But shop around to see that you're getting the best prices on things like car insurance, cable, etc.
Cleaning: Old basic cleansers like bleach and ammonia cost the least and work the best. Granted, it may not be worth using ammonia because of the smell, and you can't overdo the bleach around the rabbit. But disposable wipes and sprays cost much more to use.
Food: Get the weekly sale circulars and write a list of what's on sale (that you'd want to buy) at each store. Also clip coupons. Then shop for what's on sale. Keep away from convenience foods such as frozen dinners and canned stuff. You save a lot and get much better quality by making your own. Really, you can afford steak (or to eat out now and then) if you give up the frozen dinners.
Check your receipts before leaving the store. Stores OFTEN overring you, either by ringing the full price for something on sale, or by leaving a sale sign up after it's over (in the US, they have to give us the sale price if they leave the sign up), or whatever. Here, many stores will refund the entire cost of the item, so you get it free, not just a refund of the overring.
You might save more by moving. Do you need two bedrooms for one couple? I don't know what a "terraced house" is, but does it mean there's a place to grow some of your own fruits and vegetables next summer? That would save money, and you could swap or sell the extras for other things.
Eating out, shopping, etc. You can get some of this for free and be paid a small amount, too, if you get into mystery shopping or secret shopping. You'd have to follow the instructions you're given, then submit a report, usually online, then it's a month or so before you're reimbursed for the expenses (only what you pay for the items you purchase - never fees to just be a shopper) and paid. But you can do fast food, fine dining, and even bar and club shops as well as shops for gasoline, clothes, gifts, office supplies, etc. This website lists reputable mystery shopping companies and has info on how it's done: http://www.mspa-eu.org/