Pixel peeping advice please

My 16 yr old daughter has just enrolled for a photography course and I bought her a 'refurbished ' 350D from the Canon UK retail outlet on ebay. It arrived yesterday and appears to be a new camera. I was at the theatre last night and didn't have much time to inspect it, but I did a couple of shots of my garden in the daytime and a couple of shots last night with the lens cap on; one at 1/125th sec, the other at 30 seconds (thirty). Apart from the 30 second shot they seem fine , but the 30 second one has a distinct blue spot on it when viewed at 50% in rawshooter. I will do more tests tonight but have no other dslr at the moment and no experience of these things. Can anyone tell me if dodgy pixels are to be expected on a 30 second exposure? As I say, the other shots seem fine and have no marks in the same place, even when viewed at 200%. I have until next Wednesday to get the camera back to them for a full refund, so I need to act reasonably fast.

Yes, stuck pixels are the reality with all dslr. Some have more, some less. But in the end, it doesn't matter. I have maybe 5-15 hot pixels depending on ISO/Time.
But once you print the picture, it won't show. 5 pixels on 8 millions is a perfectly good
sensor.

Don't worry about it, and don't judge all your photo at 100%. Print them. Only then you can finally admire a good shot.

Pixel peeping advice? Just say no.