From those I've talked to, the general consensus is that 2nd year is quite a bit more difficult than first year. I think for the most part just because there's more new material to learn in every lecture. Here were my classes:

First semester:
Bio 2290F
Stats 2244A
Biochem 2280A
Chem 2213A
German 1030

Second semester:
Bio 2832B
Bio 2581B
Chem 2223B
Microimm 2500B
German 1030

First semester was pretty brutal. The 2290/stats combo is not pleasant with everything else, because stats is frustrating for most people and 2290 is just really time consuming for certain units. Moving one of those to 2nd semester may be a good idea depending on your electives and whether you're taking chem 2223B. I was so thankful to have German because it wasn't a memorization course and required far less time than the rest of my courses. There are people who take phys 2130 as an elective but I'm pretty sure I would have had a mental breakdown if I'd done that (note I was also sophing and doing other extracurriculars). So my advice is pick an elective that you think you'll enjoy and that has a relatively light workload because it's likely you'll be doing more homework in general next year. If you're interested in languages, German 1030 is a great course. Microimm 2500B was also super cool. Not easy, but interesting. I also took pharm 2060B online this year and it's not too demanding but a lot of memorization for the final.

Regarding summer school, take a look here: http://www.uwo.ca/bmsc/adjudication.html. If you still have questions, I'd check with the academic counsellors.

Your first semester will be tough so I guess my main advice would be not to take on too many extracurriculars. I was sophing, playing on a couple flag football teams, and training for a half marathon, which I managed but it wasn’t pretty.

For orgo, go to every class and do NOT fall behind (on the concepts anyway… after midterms I’m pretty sure it’s impossible to be caught up on all the practice questions). Most material builds on the previous class, so if you miss a lecture it can be difficult to understand the next one.

For 2290, the most demanding units are Gray and Krajnyk. Gray’s unit is the writing section, and I had this first, which made for a tough start to the year but I got it over with instead of having to do all the work during midterms. If you want the hardest sections first and last, sign up for section 10, 11, or 12. For the past 5+ years those sections have the order Gray, Zab, Dean, Krajnyk. I’m not sure how the order for the rest of the sections works.

Stats (as of fall 2010, but I’ve heard it hasn’t improved): the eBook is useless in my opinion, as are most lectures (except they had clicker questions). I learned basically everything out of the book. Work together in labs, it’s the only way to have any chance of understanding the questions.

Microimm 2500B and Pharm – First of all, note that Microimm 2100A is required for an HSP Microimm. Between Micro 2500B and Pharm 2060, pharm definitely felt like a lighter course (and was easier), but was not as interesting. I found micro really cool, talking about all the different bacteria and viruses and prions (so crazy!). There are two midterms if I remember correctly, both in-class. Second one fell right before cell bio and genetics = not fun. I took pharm in third year (with a lighter courseload than second year) and it was nice because it was online and I could watch the lectures whenever. And the first half of the course is quite easy. Both courses require a lot of memorization, so by the sounds of it that should suit you. Remembering symptoms (required for both courses) is difficult though because they are often somewhat random and they overlap with other diseases/pathogens. Hard to keep them all straight.

Let me know if you’ve got any other questions. I’m happy to answer them :)