I've used numerous installers for my PC:
- Wubi
- tried both X64 and the X86 bit versions
- tried to install ubuntu from a stick or a cd
but it all comes down the the wonderfull violet loading screen 'Ubuntu' with 5 flashing dots under it and it gets stuck there.
Previously, under a different version of windows 7, I managed to install Ubuntu 11.10 but there was some issue with the internet connection (device firmware missing or something like that) and there was nothing I could do to get it to connect to the internet - I'm using a wi-fi connection.
12.04 doesn't get passed the loading screen. I've tried using the option ACPI workarounds, and everything goes ok till it reaches the internet drivers for my wlan board, and it states something about downloading the proper wireless drivers. I've no idea if this is the issue of if this helps you guys but I'd really like to try ubuntu 12.04 and right now I have no means of doing so.
I'd like to make one more mention because people don't seem to understand. It simply gets stuck when I try to boot from the Ubuntu CD/stick/wubi into Ubuntu. I don't get an option to choose anything because I don't really get to start Ubuntu on my machine.
Here is a screenshot of my system:

