Vista install and no drivers

I just bought a new Dell XPS8100-3007. It came with Windows 7, but i have to run Vista, because a program i use for research purposes will not operate in 7.

I installed Vista and i can not change the screen settings and it will not detect the internet (wireless or LAN). it is as if NONE of the original drivers are available to the new (old) OS.

Please help ASAP!

thank you in advance,
Roberto

Welcome
Windows 7 Compatibility: Software Programs & Hardware Devices: Find Updates, Drivers, & Downloads
First lets see if its compatible

Then you may need to run in compatilbity mode
http://windows.microsoft.com/en-US/windows7/Make-older-programs-run-in-this-version-of-Windows