Sounds like a fun outting! Good on you for trying something new.
Night photography is hard if you cant properly control your camera.
When you said you were playing with the shutter speed, what settings where you playing with?
You definatly had the right idea in locking down the ISO, however, the point of using a tripod is so that you can get long exposures...ie not worry about shutter speed.
Can you control the aperture of your camera? If so, thats a better way to go... lock ISO to 80, set aperture to f8 - f16 and find a fun subject.
Quick cc
1- I dont find the subject to be interesting. Well exposed.
2- Out of focus \ blurry. The branch in the upper left is distracting. The photo could be improved by getting closer to your subject, whatever it was supposed to be, and fill the frame more with it. Things that dont add to the image should not be inthe image.
3- probably my fave of the set. I like the colours and tones. I dont like the sky (or lack of). Great lines in the images, and a fun subject.
4 \ 5 - nice use of lines to lead the viewers eye. However, fromt he size of the picture, looks out of focus \ blurry. If you were using a tripod, should not be a reason for this. In #5, I find there is too much going on for my eye to be drawn in...the main thing i like is the upper part of the image, the bottom isnt as nice. While i get you were trying to capture lines and such, doing too much can hurt the image
6- is just screaming out for some human interest...someone reading, sleeping, tying their shoe.... not a bad capture, but im not a fan of the reflection in the window.
Night photos can be very hard, but you are definatly on the right path. But you are making it harder for yourself with a P&S camera
