Struggling to Install

Hi Guys, first off I would like to apologise that yet another thread is being opened about this sort of thing but I cannot seem to find one that solves my problem.
As you can guess I am having troubles getting to installation, in fact I can't even get LiveDVD to boot properly. When I burn the ISO onto DVD (have tried with Windows ISO burner and PowerISO) and boot the disc I get to the LiveDVD screen where you select liveboot, memtest, etc and when I select liveboot it starts to load then I get the error "isolinux: Disc Error 04, AX = 4200, Drive FE" and it fails there. I read that it could be the DVD so I have tried on different burners but get the same result - not had a chance to get to the shops so not been able to try different brand DVDs just yet.
So I assumed it was something I was doing wrong so went with the USBboot instead. First I tried PowerISO again but that was a glorious failure and so used the unetbootin tool provided. First USB drive didn't work - it wouldn't get recognised properly during startup - but managed to get the second one to get somewhere. The laptop will try to boot the USB and it shows the line saying who it is by and the copyright and I would usually expect a message along the lines of "press any key to boot" but this doesn't turn up and I left it for a good 5-10 minutes. Maybe I am just being impatient with this?
Anyway I am now at a loss as to what it could be and what to try so was hoping for some input from the gurus out there. If it turns out that I just have one of those freak systems that refuses it then I suppose I will just have to deal with that fact but I'm hoping someone will have a solution.

For the record, I'm using an Acer 6935G with Core2Duo T9550 (2.66 Ghz, 6MB L2 Cache), 4GB RAM, WD Caviar Black HDD, Slimtype BluRay Drive and DVD multirecorder, and a 32GB Sony Microvault USB Flash Drive. Current OS is Win7 x64

Many thanks in advance

Yeah I've checked the checksum and redownloaded about 5 times now and all times it's bee fine. I looked up the code and it all seems to point to bad discs or bad burns so will try again on a third machine and see if I get anywhere.
Don't suppose you have any idea why the USB Drive won't work?

Cheers

Still no luck after trying a third burner to make the disc. very strange and very frustrating

I'll give that a go then. Ironically I had Ubuntu up and running on this system with openfoam and paraview the other week but uninstalled when I found this! c'est la vie