As I have knocked through from the living room to the dining room in my
Victorian terrace I have to replace a fair amount of skirting board.

The skirting board is just under 7 inches deep.

What kind of mitre saw will tackle this? I had a look on the HSS Hire
website but am not sure what to go with.

Would the "Crosscut & Mitre Saw" (code 03431) do the job?

Also, what do you guys recommend as the best way to refix the skirting
board. The walls are fairly uneven so I'm not keen on using Gripfil. I am
leaning towards screwing the skirting on. Does that sound OK?