if i was hunting rare tiger's to extinction in the Himalayas in the dead of summer would they hold up to the jungle?

Danner Men's Fort Lewis 10 inch 200G Gortex Law Enforcement Boot. Expensive, yes, but they will just start breaking in in ten years and will last over 20 years. Even though they have thinsulate, I have trekked them through North Carolina's toughest during the muggiest, hottest Carolina August with no complaints. 10" of breathable water proof Gortex. Steel shank. Vibram® Kletterlift outsole. They were recommended to me 30 years ago by a Green Beret. Bushwhacking though tough terrain when your life depends on it, this is the boot. Otherwise, I wear these Timberland boots every day and have put them through the worst the Linville Gorge Wilderness has to offer. They will last you two to five years depending on activity level. both are very good recommendable boots. We don't hunt Tiger's to extinction and the only thing I have ever had to do with the Himalayas and the Riff Valley, I did in Amsterdam, Holland. Wearing these Chocorua's in black. Black is recommended for European travels, unless you want every scoundrel to know you are a tourist. As for the Timberland

are they full water proof, or just water resistant?

These are water resistant. They hold up to walking through dewy grass and keep your feet dry, but stomping through streams or long hike in heavy rain results in wet socks. They're leather, so they can be oiled to improve their water resistance.

Would these be any good for everyday snow shoveling?

Yes, they are perfect boots for shoveling snow. If you are in deep snow, get some gaiters and you have an awesome set of snow boots. Be sure to care for your boots by using a silicone rub such as kiwi minkoil. By the way, in the last 6 years I have been through 4 pairs of these awesome boots. I use them for my job (package delivery) and use them for outdoor activities like 5-15 mile hikes. Get some SOLE Ultra insoles and these puppies will keep your feet painfree especially if you are on you feet for 10-15 hours/day. The only bad part is that the tread wears out pretty fast. But that is probably my fault because I cover so many miles (~300 miles/pair) on them on the concrete, asphalt and mountain trails. I'll stop there, I love these boots and hope they never change them!!

I need boots for trekking in a tropical jungle like Roraima for a week, I need them to be waterproof and to protect my ancle, is this a good choice?

I bought mine 8 years ago (2013) and up to this date it is still waterproof. The GoreTex material is still intact and yes it's been through a lot of hiking trips, camping, kayaking, fishing you name it. I used it in the rainy season in the tropics too. Not sure the one they are selling now if they upgraded or downgraded the quality to keep up the cost. BTW I got mine for $68.99.