Main reason I didn't recommend Apple is because he doesn't seem to be trying to get into it professionally. True, most use macs to do video editing, but a PC can do just about anything a mac can do, just may take a few more seconds of "thinking" The downside list to macs would far outweigh their upsides for someone that wants to edit family videos etc. and use the computer for other everyday uses (games, www, etc) Alienware does make a good computer, but they do charge a premium for their systems.
If you can build it yourself, I think thats always the best way to go. Individual parts have warranties, just make sure all the parts you buy have 1 or more year warranties. Worst case scenario you have to pull a part yourself, but then again, I don't know if companies still do on site tech support anyways since it has been so long since I bought a pre-made system.
