Premiere XL Series 4 will not boot

My Premiere XL Series 4 will not boot.

It displays the following messages during startup:

Welcome! Starting up...

Almost there... Just a few minutes more...



Previous symptoms were random re-boots, video freezes, video pixellation, sluggish or nonresponsive to the remote and stuttering.



I suspect a hard drive failure. It currently has a 1TB hard drive. I would like to purchase and install a 2TB hard drive that I spotted on Amazon. It's a Western Digital WD AV-GP 2 TB AV Video Hard Drive: 3.5 Inch, SATA II, 64 MB Cache – WD20EURS.



My Tivo is out of warranty.



Will this hard drive work in my Tivo? How do I install the Tivo software on the new drive? Where do I obtain the Tivo software?



Thanks for any help that you can give me.