Travel to Verona, Venice

I want to travel from UK to Verona, and Venice by train, using Eurostar, and probably a sleeper from Paris .
Can anyone advise on the best place to book, and whether to use an agent, Railbookers, Raileurope etc. I'm happy to book independently, but the Italian Rail website I found un-user friendly, and I'm not confident I'd be able to book what I want.
Is it really worth travelling via Switzerland or Germany to Verona for the Alpine scenery.
Lastly does the overnight Paris Verona sleeper stop at Peschiera on Lake Garda?

Thanks for any help

The easy question first - the Paris to Venice sleeper does not stop at Peschiera del Garda; it runs non-stop between Brescia and Verona.

Going via Switzerland obviously takes longer, and will be more expensive. An alternative route to Verona would be to travel to Munich (via Paris or Brussels), and then on an EC train (operated by DB and OeBB) to Verona. If you travel via Brussels, it will probably be cheaper, because you can get a through DB ticket to Munich - you can book this and the EC train on the DB website. Personally, I enjoy the trip down through the Dolomites to Verona, although you see less scenery than you used to, because of the long tunnels south of Brenner and north of Bolzano.

Regarding the trenitalia website, I have used it several times to buy tickets without any problem - if you have specific issues, maybe you can point them out.

I've never used the agencies, so can't comment on them, because I always buy online wherever possible.

I have booked in advance to use the TGV from Paris Lyon to Milan Centrale where I connect into a high speed service to Verona.

The TGV leaves Gar Lyon at 0742 and rolls into Milan at 1450. The connection for Verona leaves Milan at 1505 with and arrival at 1627 in Verona.

I booked about 8 weeks in advance and got a fare of £76 Paris to Milan in first class. Second class was about the same price. The fare through to Verona added another 18 Euros for 2 people in first class using the two for the price of one weekend fares purchased in advance. Total cost paris to Verona around £84 in first class - not bad eh?