Multi-Talk 75 is an add-on minutes bundle for the phone package for calls not covered by their talk plan.
You should find more detail in the latest call costs tariff files at the bottom of this page:
http://www.virginmedia.com/shop/phone/compare.html
Fibre 20Mbs is the slowest speed Virgin now offer on retentions packages. (Lowest speed on normal packages is now 100Mbs). It looks like the package they have has not been changed in a while. If you don't renegotiate packages regularly prices will continuously rise.