The Canon 450D is a great camera that won't be too big to carry around, or use if your wife has small hands (though you can still get the 400D from a few places for a fair bit less and that's also a great camera. If you buy the 450D as a part of a kit then it works out that you get the kit lens for about half price. The kit lens will most often be a standard zoom (covering wide angle to the normal range (equivalent field of view (fov) to short telephoto on a crop camera)). Most people find they use the 17-55mm range more often than anything else and so something in that range is generally worthwhile (just be prepared to upgrade the kit lens when you get into it more as once you do and start pushing it you'll eventually outgrow it, but when you're on a budget a lens costing under £50 can do the job in the short term).
Canon EOS 450D + 18-55mm IS kit lens = £444.50
Considering the price of the 50mm f1.8 it's worth everyone who starts out getting one, as it's a cheap, fast and versatile fixed focal length (prime) lens. On a full frame camera the fov is considered normal as it's supposed to give the same approximate fov as human vision. On a crop camera it gives a longer equivalent fov though, at 80mm equivalent, but that's also a great length for portraits.
EF 50mm f/1.8 = £68.19 (
available cheaper elsewhere if you trust the shops)
Tripods can be expensive, and they get more expensive the lighter, sturdier and more feature rich they become. But based on budget constraints and unless you start buying heavy kit such as a 300mm f/2.8 the Manfotto 190X should be capable enough:
Manfrotto 190XProB Tripod = £89.99
Whatever tripod you get you're also going to need a good head to go with it. Whether you prefer a ball head or a 3 way pan/tilt type is up to your personal preference, but I prefer ball heads. Sticking with the same provisos as mentioned for the tripod, I'd recommend the same head as Sarah has. It's small, light and flexible but will still support up to 6kg of weight. It's also inexpensive as far as ball heads go.
Manfrotto MN486RC2 Compact Ball Head = £39.99
As for bags - I have a few, and you'll probably eventually find that you have a selection that you use for different purposes. So decide how you want to carry your kit around now and then buy based on that. You have essentially 5 main options (excluding heavy duty stuff like Peli cases) - a backpack, day pack, a sling bag, shoulder bag, messenger style bag.
A back pack is great when you're out hiking doing nature photography, there's a large range of sizes but even the smallest will carry an SLR with several lenses and accessories. I can recommend both Loweprowe and Kata bags as being very high quality, but I wouldn't discount Tamrac either as they have a good rep.
The day pack type bags have a camera compartment as well as a 'personal' compartment for a pack lunch, jacket, change of shirt or whatever. Sarah has a lowepro orion trekker which is a very nice bag, but I can't seem to find at Warehouse Express any more. I have a Kata DR465 which is great. It's very sturdy, the main camera compartment will hold 3 lenses along with a 40D with grip attached and a few accessories. There's a drink bottle holder which can double as a monopod holder, the main compartment is big enough for a jumper, anorak and a pack lunch, and there are a 3 other accessory pockets - there's also a bigger version of this with a laptop compartment and more space in the other compartments.
Slingbags are useful when you want to carry your kit on your back but need quick access to it - such as while cycling. They're quite versatile, but if you put a lot of heavy kit in them they can become a strain, however I regularly carry my 40D + grip, 3 lenses, filters, cleaning kit and other accessories in my Lowepro 200AW slingshot without it being an issue for me.
Messenger bags (I'm specifically talking Crumpler here, but there may be other similar brands) seem to be as much about style as function to me, and some reviews suggest they aren't the best if you get caught in heavy rain. However I do want one for carrying a small kit (body and 2 lenses) around town. But from everything I've read about them they aren't what I'd suggest as a first or primary camera bag.
Shoulder bags are possibly perceived as the more traditional type of camera bag, and some brands do market themselves as that (Billingham, Domke etc), but others have shifted from the traditional look and gone for more modern, but functional, styles. I like the look and features of several Lowepro, Tamrac, Hama and Kata shoulder bags, and when I need a larger one I'll likely be shortlisting the Lowepro Magnum and Kata Reporter bags with Kata maybe being the slight favourite as I have 2 Kata bags already and I'm very impressed with the quality. Until then I'm very happy with my Kata DC445 which, while not big and bulky, easily coped with everything I needed to take to Ireland with me last weekend (large dslr + grip and a lens attached with hood reversed, a small film slr with 50mm lens attached and hood reversed, a third lens with hood reversed and a lot of accessories), it was comfortable to carry and didn't get in the way when going around shops which a back pack would have done.
Kata DC445 shoulder bag = £51.95 - currently out of stock at WH, but if you can find it elsewhere it's a great bag (you can get it free from Practical Photography mag if you subscribe now, quote HSAA when phoning)
Other recommendations will depend heavily on what you want to shoot and how you want to shoot it as SL said. An alternative to a standard zoom might be a wide angle prime if you prefer a fixed focal length instead of a zoom, such as a 20mm or 28mm; or instead of the 50mm something around 30mm will give the 'normal' fov on a crop camera. If you want to go telephoto there are some fantastic but expensive options, cheap options are harder to find once you get past 50mm, but until I can justify the cost of a 70-200mm I'm happy with my 75-300mm which is pretty cheap at under £200. A lot of people slate it as crap, but I've had great results from mine and have sold prints from it. It does have its shortcomings, but if you can learn to work around those it's worth considering.
Edited to add ball head info.
