I have a Dell Latitude C640 with the following specs:
2 gHz Pentium 4 Processor
512MB RAM

if more info is needed, i will add at request

Go out and spend $50 on a hard drive for your laptop (make sure you open it up and find out if SATA or IDE).

and then try.

Dell's seem to work ok, I have 10.6.6 running (can't update to 10.6.7 or 10.6.8 without kernel panics).

Basically I used Xboot, then waited for disc to stop then put in the retail snow leo dvd, hit F5 twice, then got to install screen went to disc utility and created 2 partitions of equal size. One for OSX and one I called storage (for time machine back up).

LAN works (with kexts) and graphics resolution is stuck on 1024x768 (still working on this).

Honestly the best way to know if it will work is to try, go to an Apple store, or best buy or buy a retail dvd for snow leopard online and then go get xboot and try it out.