I've decided to buy one of
those but can't decide on which one to go with.
Please help me out, any reasoning and hints would be great.
*
Budget
Not above £1300 for any of them including two kit-lenses.
Size
Doesn't matter. They're almost the same size and the difference is none for me. Sony is somewhat heavier but it also doesn't bother me.
How many megapixels will suffice for you?
8 or 10?

Would seldom print out images that are larger than an a4, but it would be nice to have the option is I wanted to. Also, cropping an image would be easier with 10 I guess.
How important is “image quality” to you? (Rate using a scale of 1-10)
10, also only reason why I'd go with the Sony since the 350 has rave reviews and most are very happy with it.
Do you care for manual controls?
Who doesn't?
What will you generally use the camera for?
All around, mostly peeople, snapshots. etc.
Will you be making big prints of your photos or not?
Plenty of times about a4 in size. Sometimes larger if possible. However I'd rather have better quality cam than the possibility to make huge printes of semi-crappy shots.
Will you be shooting a lot of indoor photos or low light photos?
Yes.
Will you be shooting sports and/or action photos?
Not often, if snapshots aren't included, which they are.
Are there particular brands you like or hate?
I'm very interested in Canon but since I don't have any lenses already I'm free to buy whatever brand. Decided that I want one of these two models, brand doesn't matter - quality of the picture does.
Are there particular models you already have in mind?
Canon EOS 350D / Sony a100
(If applicable) Do you need any of the following special features? (Wide Angle, Image Stabilization, Weatherproof, Hotshoe, Rotating LCD)
I've never shot with image stabilization before. Only digital camera I've had was Minolta Dimage 7Hi (which died on me 3 days ago, hence I want a real one now...) so I don't know if I need it - probably do
if it works very well in lowlight/indoors.
I loved the possibility to change the position / angel of the viewfinder and the a100 has an extra thing (FDA-A1AM) that you can buy that enables you to do so. It amazes me that so few cameras have that per default in their construction - once you try it out you'll never want to be without it. Haven't seen that option for 305D - does it even exist?
The anti-dust function in the sony doesn't interest me and is not a plus from my perspective. Neither is carl zeiss since I won't ever afford those :P