[Shiraz (Ray)]

the 120 is a better bet than the 034 (more pixels makes finding the target easier). It has a good reputation with the planetary imaging crowd. Maybe also consider the QHY5L2 which has the same chip.

It should fit straight in the scope via the 1.25 inch nosepiece (in place of an eyepiece). Use it at f10 for lunar imaging or with a standard 2x barlow for planetary imaging at f20. The mount should be able to track well enough to do the job for image sequences of at least a few minutes.

There is plenty of free software for it that is very comprehensive, but a bit complex to start with. Recommend Firecapture for getting the images and Autostakkert for stacking and processing them. Registax is also very good (especially for sharpening images) and something like GIMP or photoshop is useful for prettying up the final images.

I could be wrong, but I don't think that the 1100D supports raw video capture of a sub region on the chip, so it would not be very suitable for planetary imaging - where you will want to gather and stack hundreds (or even thousands) of frames at 30+ frames per second to reduce turbulence effects.

it will be frustrating getting it all to work and you will need to ask a few questions here, but it will be fun when you get that first sharp image of the moon.