"Dell" tells me nothing. You can install Lion on a PC that meets the system requirements on Lion, which are as follows:
x86-64 CPU
At least 2GB of RAM
Mac OS X 10.6.6 or later (Mac OS X 10.6.8 is recommended)
At least 7 GB of free hard drive space
It may be possible to install it without first installing Leopard or Snow Leopard. I'm not sure. You will probably have to install Unix as well, I'm also not sure about that. In any case, it will be a massive pain in the ass and more trouble than it's worth, but if you really want to, go for it. Education is good for you.
